Statistics is the study of the collection, analysis, interpretation, presentation, and organization of data. In applying statistics to, e.g., a scientific, industrial, or societal problem, it is conventional to begin with a statistical population or a statistical model process to be studied. Populations can be diverse topics such as "all persons living in a country" or "every atom composing a crystal". Statistics deals with all aspects of data including the planning of data collection in terms of the design of surveys and experiments. Descriptive statistics are most often concerned with two sets of properties of a distribution : central tendency seeks to characterize the distribution's central or typical value, while dispersion characterizes the extent to which members of the distribution depart from its center and each other. Inferences on mathematical statistics are made under the framework of probability theory, which deals with the analysis of random phenomena.
Standard statistical procedure commonly involve the development of a null hypothesis, a general statement or default position that there is no relationship between two quantities. Rejecting or disproving the null hypothesis is a common task in the modern practice of science, and gives a precise sense in which a claim is capable of being proven false. What statisticians call an alternative hypothesis is simply a hypothesis that contradicts the null hypothesis. Working from a null hypothesis, two basic forms of error are recognized: Type I errors and Type II errors . Multiple problems have come to be associated with this framework: ranging from obtaining a sufficient sample size to specifying an adequate null hypothesis.
Measurement processes that generate statistical data are also subject to error. Many of these errors are classified as random or systematic, but other important types of errors can also be important. The presence of missing data and/or censoring may result in biased estimates and specific techniques have been developed to address these problems.
Statistics can be said to have begun in ancient civilization, going back at least to the 5th century BC, but it was not until the 18th century that it started to draw more heavily from calculus and probability theory. Statistics continues to be an area of active research, for example on the problem of how to analyze Big data.
Scope
The R's Academy provides you the Notes on any Academic Subject, which will be helpful for Passing out you Exams and for personal Informations.
Wednesday, June 24, 2015
What is Management
Management in businesses and organizations is the function that coordinates the efforts of people to accomplish goals and objectives using available resources efficiently and effectively.
Management includes planning, organizing, staffing, leading or directing, and controlling an organization to accomplish the goal. Resourcing encompasses the deployment and manipulation of human resources, financial resources, technological resources, and natural resources. Management is also an academic discipline, a social science whose objective is to study social organization.
Etymology
The verb 'manage' comes from the Italian maneggiare, which derives from the two Latin words manus and agere .
In that course, the French word ménagerie, derived from ménager, for housekeeping also encompasses taking care of domestic animals.
Later, mesnagement influenced the development in meaning of the English word management in the 17th and 18th centuries.
Thus, it should be noted that Ménagerie is the French translation of Xenophon's famous book Oeconomicus on household matters and Husbandry.
While the Italian word maneggiare refers to subaltern responsibilities, the work of an executive would be described as gestire.
Definitions
Views on the definition and scope of management include:
According to Henri Fayol, "to manage is to forecast and to plan, to organise, to command, to co-ordinate and to control."
Fredmund Malik defines it as "the transformation of resources into utility."
Management included as one of the factors of production - along with machines, materials and money
Peter Drucker saw the basic task of a management as twofold: marketing and innovation. Nevertheless, innovation is also linked to marketing . Peter Drucker identifies marketing as a key essence for business success, but management and marketing are generally understood as two different branches of business administration knowledge.
Andreas Kaplan specifically defines European Management as a cross-cultural, societal management approach based on interdisciplinary principles.
Directors and managers should have the authority and responsibility to make decisions to direct an enterprise when given the authority
As a discipline, management comprises the interlocking functions of formulating corporate policy and organizing, planning, controlling, and directing a firm's resources to achieve a policy's objectives
The size of management can range from one person in a small firm to hundreds or thousands of managers in multinational companies.
In large firms, the board of directors formulates the policy that the chief executive officer implements.
Theoretical scope
Management involves identifying the mission, objective, procedures, rules and the manipulation of the human capital of an enterprise to contribute to the success of the enterprise. This implies effective communication: an enterprise environment, implies human motivation and implies some sort of successful progress or system outcome. As such, management is not the manipulation of a mechanism, not the herding of animals, and can occur in both a legal as well as illegal enterprise or environment.Management does not need to be seen from enterprise point of view alone, because management is an essential function to improve one's life and relationships. Management is therefore everywhere and it has a wider range of application. Based on this, management must have humans, communication, and a positive enterprise endeavor. Plans, measurements, motivational psychological tools, goals, and economic measures may or may not be necessary components for there to be management. At first, one views management functionally, such as measuring quantity, adjusting plans, meeting goals. This applies even in situations where planning does not take place. From this perspective, Henri Fayol
considers management to consist of six functions:
# Forecasting
# Planning
# Organizing
# Commanding
# Coordinating
# Controlling
Henri Fayol was one of the most influential contributors to modern concepts of management.
In another way of thinking, Mary Parker Follett, defined management as "the art of getting things done through people". She described management as philosophy.
Critics, however, find this definition useful but far too narrow. The phrase "management is what managers do" occurs widely, suggesting the difficulty of defining management, the shifting nature of definitions and the connection of managerial practices with the existence of a managerial cadre or class.
One habit of thought regards management as equivalent to "business administration" and thus excludes management in places outside commerce, as for example in charities and in the public sector. More broadly,every organization must manage its work, people, processes, technology, etc. to maximize effectiveness. Nonetheless, many people refer to university departments that teach management as "business schools". Some institutions use that name while others employ the more inclusive term "management".
English speakers may also use the term "management" or "the management" as a collective word describing the managers of an organization, for example of a corporation. Historically this use of the term often contrasted with the term "Labor" - referring to those being managed.
But in the present era management's use is identified in the wide areas and its frontiers have been pushed to a broader range. Apart from profitable organizations even non-profitable organizations apply management concepts. The concept and its uses are not constrained. Management on the whole is the process of planning, organizing, staffing, leading and controlling.
Nature of managerial work
In profitable organizations, management's primary function is the satisfaction of a range of stakeholders. This typically involves making a profit, creating valued products at a reasonable cost, and providing great employment opportunities for employees. In nonprofit management, add the importance of keeping the faith of donors. In most models of management and governance, shareholders vote for the board of directors, and the board then hires senior management. Some organizations have experimented with other methods of selecting or reviewing managers, but this is rare.
In the public sector of countries constituted as representative democracies, voters elect politicians to public office. Such politicians hire many managers and administrators, and in some countries like the United States political appointees lose their jobs on the election of a new president/governor/mayor.
Historical development
Some see management as late-modern conceptualization. On those terms it cannot have a pre-modern history, only harbingers . Others, however, detect management-like-thought back to Sumerian traders and to the builders of the pyramids of ancient Egypt. Slave-owners through the centuries faced the problems of exploiting/motivating a dependent but sometimes unenthusiastic or recalcitrant workforce, but many pre-industrial enterprises, given their small scale, did not feel compelled to face the issues of management systematically. However, innovations such as the spread of Hindu numerals and the codification of double-entry book-keeping provided tools for management assessment, planning and control.
With the changing workplaces of industrial revolutions in the 18th and 19th centuries, military theory and practice contributed approaches to managing the newly-popular factories.
Given the scale of most commercial operations and the lack of mechanized record-keeping and recording before the industrial revolution, it made sense for most owners of enterprises in those times to carry out management functions by and for themselves. But with growing size and complexity of organizations, the split between owners and day-to-day managers gradually became more common.
Early writing
While management has existed for millennia, several writers have created a background of works that assisted in modern management theories.
Some ancient military texts have been cited for lessons that civilian managers can gather. For example, Chinese general Sun Tzu in the 6th century BCE, The Art of War, recommends being aware of and acting on strengths and weaknesses of both a manager's organization and a foe's.
Smith described how changes in processes could boost productivity in the manufacture of pins. While individuals could produce 200 pins per day, Smith analyzed the steps involved in manufacture and, with 10 specialists, enabled production of 48,000 pins per day.
20th century
By about 1900 one finds managers trying to place their theories on what they regarded as a thoroughly scientific basis . Examples include Henry R. Towne's Science of management in the 1890s, Frederick Winslow Taylor's The Principles of Scientific Management, Lillian Gilbreth's Psychology of Management, Frank and Lillian Gilbreth's Applied motion study, and Henry L. Gantt's charts . J. Duncan wrote the first college management-textbook in 1911. In 1912 Yoichi Ueno introduced Taylorism to Japan and became the first management consultant of the "Japanese-management style". His son Ichiro Ueno pioneered Japanese quality assurance.
The first comprehensive theories of management appeared around 1920. The Harvard Business School offered the first Master of Business Administration degree in 1921. People like Henri Fayol and Alexander Church described the various branches of management and their inter-relationships. In the early 20th century, people like Ordway Tead, Walter Scott and J. Mooney applied the principles of psychology to management. Other writers, such as Elton Mayo, Mary Parker Follett, Chester Barnard, Max Weber, who saw what he called the "administrator" as bureaucrat), Rensis Likert, and Chris Argyris approached the phenomenon of management from a sociological perspective.
Peter Drucker wrote one of the earliest books on applied management: Concept of the Corporation . It resulted from Alfred Sloan commissioning a study of the organisation. Drucker went on to write 39 books, many in the same vein.
H. Dodge, Ronald Fisher, and Thornton C. Fry introduced statistical techniques into management-studies. In the 1940s, Patrick Blackett worked in the development of the applied-mathematics science of operations research, initially for military operations. Operations research, sometimes known as "management science", attempts to take a scientific approach to solving decision-problems, and can apply directly to multiple management problems, particularly in the areas of logistics and operations.
Some of the more developments include the Theory of Constraints, management by objectives, reengineering, Six Sigma and various information-technology-driven theories such as agile software development, as well as group-management theories such as Cog's Ladder.
As the general recognition of managers as a class solidified during the 20th century and gave perceived practitioners of the art/science of management a certain amount of prestige, so the way opened for popularised systems of management ideas to peddle their wares. In this context many management fads may have had more to do with pop psychology than with scientific theories of management.
Towards the end of the 20th century, business management came to consist of six separate branches, namely:
# financial management
# human resource management
# information technology management
# marketing management
# operations management or production management
# strategic management
21st century
In the 21st century observers find it increasingly difficult to subdivide management into functional categories in this way. More and more processes simultaneously involve several categories. Instead, one tends to think in terms of the various processes, tasks, and objects subject to management.
Branches of management theory also exist relating to nonprofits and to government: such as public administration, public management, and educational management. Further, management programs related to civil-society organizations have also spawned programs in nonprofit management and social entrepreneurship.
Note that many of the assumptions made by management have come under attack from business-ethics viewpoints, critical management studies, and anti-corporate activism.
As one consequence, workplace democracy has become both more common and advocated to a greater extent, in some places distributing all management functions among workers, each of whom takes on a portion of the work. However, these models predate any current political issue, and may occur more naturally than does a command hierarchy. All management embraces to some degree a democratic principle—in that in the long term, the majority of workers must support management. Otherwise, they leave to find other work or go on strike. Despite the move toward workplace democracy, command-and-control organization structures remain commonplace as de facto organization structure. Indeed, the entrenched nature of command-and-control is evident in the way that recent layoffs have been conducted with management ranks affected far less than employees at the lower levels. In some cases, management has even rewarded itself with bonuses after laying off lower-level workers.
According to leadership academic Manfred F.R. Kets de Vries, a contemporary senior management team will almost inevitably have some personality disorders.
Topics
Basic functions
Management operates through five basic functions: planning, organizing, coordinating, commanding, and controlling.
Planning: Deciding what needs to happen in the future and generating plans for action.
Organizing: Making sure the human and nonhuman resources are put into place
Coordinating: Creating a structure through which an organization's goals can be accomplished.
Commanding: Determining what must be done in a situation and getting people to do it.
Controlling: Checking progress against plans.
Basic roles
Interpersonal: roles that involve coordination and interaction with employees
Informational: roles that involve handling, sharing, and analyzing information
Decision: roles that require decision-making
Managerial Skills
Political: used to build a power base and establish connections
Conceptual: used to analyze complex situations.
Interpersonal: used to communicate, motivate, mentor and delegate
Diagnostic: ability to visualize most appropriate response to a situation
Leadership: ability to lead and provide guidance to a specific group
Technical: Expertise in one's particular functional area.
Formation of the business policy
The mission of the business is the most obvious purpose—which may be, for example, to make soap.
The vision of the business reflects its aspirations and specifies its intended direction or future destination.
The objectives of the business refers to the ends or activity that is the goal of a certain task.
The business's policy is a guide that stipulates rules, regulations and objectives, and may be used in the managers' decision-making. It must be flexible and easily interpreted and understood by all employees.
The business's strategy refers to the coordinated plan of action it takes and resources it uses to realize its vision and long-term objectives. It is a guideline to managers, stipulating how they ought to allocate and use the factors of production to the business's advantage. Initially, it could help the managers decide on what type of business they want to form.
Implementation of policies and strategies
All policies and strategies must be discussed with all managerial personnel and staff.
Managers must understand where and how they can implement their policies and strategies.
A plan of action must be devised for each department.
Policies and strategies must be reviewed regularly.
Contingency plans must be devised in case the environment changes.
Top-level managers should carry out regular progress assessments.
The business requires team spirit and a good environment.
The missions, objectives, strengths and weaknesses of each department must be analyzed to determine their roles in achieving the business's mission.
The forecasting method develops a reliable picture of the business's future environment.
A planning unit must be created to ensure that all plans are consistent and that policies and strategies are aimed at achieving the same mission and objectives.
All policies must be discussed with all managerial personnel and staff that is required in the execution of any departmental policy.
Organizational change is strategically achieved through the implementation of the eight-step plan of action established by John P. Kotter: Increase urgency, get the vision right, communicate the buy-in, empower action, create short-term wins, don't let up, and make change stick.
Policies and strategies in the planning process
They give mid and lower-level managers a good idea of the future plans for each department in an organization.
A framework is created whereby plans and decisions are made.
Mid and lower-level management may add their own plans to the business's strategies.
Levels
Most organizations have three management levels: first-level, middle-level, and top-level managers. These managers are classified in a hierarchy of authority, and perform different tasks. In many organizations, the number of managers in every level resembles a pyramid. Each level is explained below in specifications of their different responsibilities and likely job titles.
Top-level management
The top consists of the board of directors, president, vice-president, CEOs and other members of the C-level executives. They are responsible for controlling and overseeing the entire organization. They set a tone at the top and develop strategic plans, company policies, and make decisions on the direction of the business. In addition, top-level managers play a significant role in the mobilization of outside resources and are accountable to the shareholders and general public.
The board of directors is typically primarily composed of non-executives which owe a fiduciary duty to shareholders and are not closely involved in the day-to-day activities of the organization, although this varies depending on the type, size and culture of the organization. These directors are theoretically liable for breaches of that duty and typically insured under directors and officers liability insurance. Fortune 500 directors are estimated to spend 4.4 hours per week on board duties, and median compensation was $212,512 in 2010. The board sets corporate strategy, makes major decisions such as major acquisitions, and hires, evaluates, and fires the top-level manager and the CEO typically hires other positions. However, board involvement in the hiring of other positions such as the Chief Financial Officer has increased. In 2013, a survey of over 160 CEOs and directors of public and private companies found that the top weaknesses of CEOs were "mentoring skills" and "board engagement", and 10% of companies never evaluated the CEO. The board may also have certain employees report to them or directly hire independent contractors; for example, the board typically selects the auditor.
Helpful skills of top management vary by the type of organization but typically include a broad understanding competition, world economies, and politics. In addition, the CEO is responsible for implementing and determining the broad policies of the organization. Executive management accomplishes the day-to-day details, including: instructions for preparation of department budgets, procedures, schedules; appointment of middle level executives such as department managers; coordination of departments; media and governmental relations; and shareholder communication.
Middle-level managers
Consist of general managers, branch managers and department managers. They are accountable to the top management for their department's function. They devote more time to organizational and directional functions. Their roles can be emphasized as executing organizational plans in conformance with the company's policies and the objectives of the top management, they define and discuss information and policies from top management to lower management, and most importantly they inspire and provide guidance to lower level managers towards better performance.
Middle management is the midway management of a categorized organization, being secondary to the senior management but above the deepest levels of operational members. An operational manager may be well-thought-out the middle management, or may be categorized as non-management operate, liable to the policy of the specific organization. Efficiency of the middle level is vital in any organization, since they bridge the gap between top level and bottom level staffs.
Their functions include:
Design and implement effective group and inter-group work and information systems.
Define and monitor group-level performance indicators.
Diagnose and resolve problems within and among work groups.
Design and implement reward systems that support cooperative behavior. They also make decision and share ideas with top managers.
Lower-level managers
Consist of supervisors, section leaders, foremen, etc. They focus on controlling and directing. They usually have the responsibility of assigning employees tasks, guiding and supervising employees on day-to-day activities, ensuring quality and quantity production, making recommendations, suggestions, and up channeling employee problems, etc. First-level managers are role models for employees that provide:
Basic supervision
Motivation
Career planning
Performance feedback
Training
Universities around the world, offer bachelor's and advanced degrees, diplomas and certificates in management, generally within their colleges of business and business schools but also in other related departments. There is also an increase in online management education and training in the form of electronic educational technology .
United States of America
At the graduate level students may choose to specialize in major subareas of management such as entrepreneurship, human resources, international business, organizational behavior, organizational theory, strategic management. accounting, corporate finance, entertainment, global management, healthcare management, investment management, Leaders in Sustainability and real estate
Current best practices
While management trends can change rapidly, the long term trend in management has been defined by a market embracing diversity and rising service industry. Managers are currently being trained to encourage greater equality for minorities and women in the workplace by offering increased flexibility in time worked, better retraining, and innovative performance markers. Managers destined for the service sector are being trained to use unique measurement techniques, better worker support and more charismatic leadership styles. Human resources finds itself increasingly working with management in a training capacity to help collect management data on the success of management actions with employees.
Management includes planning, organizing, staffing, leading or directing, and controlling an organization to accomplish the goal. Resourcing encompasses the deployment and manipulation of human resources, financial resources, technological resources, and natural resources. Management is also an academic discipline, a social science whose objective is to study social organization.
Etymology
The verb 'manage' comes from the Italian maneggiare, which derives from the two Latin words manus and agere .
In that course, the French word ménagerie, derived from ménager, for housekeeping also encompasses taking care of domestic animals.
Later, mesnagement influenced the development in meaning of the English word management in the 17th and 18th centuries.
Thus, it should be noted that Ménagerie is the French translation of Xenophon's famous book Oeconomicus on household matters and Husbandry.
While the Italian word maneggiare refers to subaltern responsibilities, the work of an executive would be described as gestire.
Definitions
Views on the definition and scope of management include:
According to Henri Fayol, "to manage is to forecast and to plan, to organise, to command, to co-ordinate and to control."
Fredmund Malik defines it as "the transformation of resources into utility."
Management included as one of the factors of production - along with machines, materials and money
Peter Drucker saw the basic task of a management as twofold: marketing and innovation. Nevertheless, innovation is also linked to marketing . Peter Drucker identifies marketing as a key essence for business success, but management and marketing are generally understood as two different branches of business administration knowledge.
Andreas Kaplan specifically defines European Management as a cross-cultural, societal management approach based on interdisciplinary principles.
Directors and managers should have the authority and responsibility to make decisions to direct an enterprise when given the authority
As a discipline, management comprises the interlocking functions of formulating corporate policy and organizing, planning, controlling, and directing a firm's resources to achieve a policy's objectives
The size of management can range from one person in a small firm to hundreds or thousands of managers in multinational companies.
In large firms, the board of directors formulates the policy that the chief executive officer implements.
Theoretical scope
Management involves identifying the mission, objective, procedures, rules and the manipulation of the human capital of an enterprise to contribute to the success of the enterprise. This implies effective communication: an enterprise environment, implies human motivation and implies some sort of successful progress or system outcome. As such, management is not the manipulation of a mechanism, not the herding of animals, and can occur in both a legal as well as illegal enterprise or environment.Management does not need to be seen from enterprise point of view alone, because management is an essential function to improve one's life and relationships. Management is therefore everywhere and it has a wider range of application. Based on this, management must have humans, communication, and a positive enterprise endeavor. Plans, measurements, motivational psychological tools, goals, and economic measures may or may not be necessary components for there to be management. At first, one views management functionally, such as measuring quantity, adjusting plans, meeting goals. This applies even in situations where planning does not take place. From this perspective, Henri Fayol
considers management to consist of six functions:
# Forecasting
# Planning
# Organizing
# Commanding
# Coordinating
# Controlling
Henri Fayol was one of the most influential contributors to modern concepts of management.
In another way of thinking, Mary Parker Follett, defined management as "the art of getting things done through people". She described management as philosophy.
Critics, however, find this definition useful but far too narrow. The phrase "management is what managers do" occurs widely, suggesting the difficulty of defining management, the shifting nature of definitions and the connection of managerial practices with the existence of a managerial cadre or class.
One habit of thought regards management as equivalent to "business administration" and thus excludes management in places outside commerce, as for example in charities and in the public sector. More broadly,every organization must manage its work, people, processes, technology, etc. to maximize effectiveness. Nonetheless, many people refer to university departments that teach management as "business schools". Some institutions use that name while others employ the more inclusive term "management".
English speakers may also use the term "management" or "the management" as a collective word describing the managers of an organization, for example of a corporation. Historically this use of the term often contrasted with the term "Labor" - referring to those being managed.
But in the present era management's use is identified in the wide areas and its frontiers have been pushed to a broader range. Apart from profitable organizations even non-profitable organizations apply management concepts. The concept and its uses are not constrained. Management on the whole is the process of planning, organizing, staffing, leading and controlling.
Nature of managerial work
In profitable organizations, management's primary function is the satisfaction of a range of stakeholders. This typically involves making a profit, creating valued products at a reasonable cost, and providing great employment opportunities for employees. In nonprofit management, add the importance of keeping the faith of donors. In most models of management and governance, shareholders vote for the board of directors, and the board then hires senior management. Some organizations have experimented with other methods of selecting or reviewing managers, but this is rare.
In the public sector of countries constituted as representative democracies, voters elect politicians to public office. Such politicians hire many managers and administrators, and in some countries like the United States political appointees lose their jobs on the election of a new president/governor/mayor.
Historical development
Some see management as late-modern conceptualization. On those terms it cannot have a pre-modern history, only harbingers . Others, however, detect management-like-thought back to Sumerian traders and to the builders of the pyramids of ancient Egypt. Slave-owners through the centuries faced the problems of exploiting/motivating a dependent but sometimes unenthusiastic or recalcitrant workforce, but many pre-industrial enterprises, given their small scale, did not feel compelled to face the issues of management systematically. However, innovations such as the spread of Hindu numerals and the codification of double-entry book-keeping provided tools for management assessment, planning and control.
With the changing workplaces of industrial revolutions in the 18th and 19th centuries, military theory and practice contributed approaches to managing the newly-popular factories.
Given the scale of most commercial operations and the lack of mechanized record-keeping and recording before the industrial revolution, it made sense for most owners of enterprises in those times to carry out management functions by and for themselves. But with growing size and complexity of organizations, the split between owners and day-to-day managers gradually became more common.
Early writing
While management has existed for millennia, several writers have created a background of works that assisted in modern management theories.
Some ancient military texts have been cited for lessons that civilian managers can gather. For example, Chinese general Sun Tzu in the 6th century BCE, The Art of War, recommends being aware of and acting on strengths and weaknesses of both a manager's organization and a foe's.
Smith described how changes in processes could boost productivity in the manufacture of pins. While individuals could produce 200 pins per day, Smith analyzed the steps involved in manufacture and, with 10 specialists, enabled production of 48,000 pins per day.
20th century
By about 1900 one finds managers trying to place their theories on what they regarded as a thoroughly scientific basis . Examples include Henry R. Towne's Science of management in the 1890s, Frederick Winslow Taylor's The Principles of Scientific Management, Lillian Gilbreth's Psychology of Management, Frank and Lillian Gilbreth's Applied motion study, and Henry L. Gantt's charts . J. Duncan wrote the first college management-textbook in 1911. In 1912 Yoichi Ueno introduced Taylorism to Japan and became the first management consultant of the "Japanese-management style". His son Ichiro Ueno pioneered Japanese quality assurance.
The first comprehensive theories of management appeared around 1920. The Harvard Business School offered the first Master of Business Administration degree in 1921. People like Henri Fayol and Alexander Church described the various branches of management and their inter-relationships. In the early 20th century, people like Ordway Tead, Walter Scott and J. Mooney applied the principles of psychology to management. Other writers, such as Elton Mayo, Mary Parker Follett, Chester Barnard, Max Weber, who saw what he called the "administrator" as bureaucrat), Rensis Likert, and Chris Argyris approached the phenomenon of management from a sociological perspective.
Peter Drucker wrote one of the earliest books on applied management: Concept of the Corporation . It resulted from Alfred Sloan commissioning a study of the organisation. Drucker went on to write 39 books, many in the same vein.
H. Dodge, Ronald Fisher, and Thornton C. Fry introduced statistical techniques into management-studies. In the 1940s, Patrick Blackett worked in the development of the applied-mathematics science of operations research, initially for military operations. Operations research, sometimes known as "management science", attempts to take a scientific approach to solving decision-problems, and can apply directly to multiple management problems, particularly in the areas of logistics and operations.
Some of the more developments include the Theory of Constraints, management by objectives, reengineering, Six Sigma and various information-technology-driven theories such as agile software development, as well as group-management theories such as Cog's Ladder.
As the general recognition of managers as a class solidified during the 20th century and gave perceived practitioners of the art/science of management a certain amount of prestige, so the way opened for popularised systems of management ideas to peddle their wares. In this context many management fads may have had more to do with pop psychology than with scientific theories of management.
Towards the end of the 20th century, business management came to consist of six separate branches, namely:
# financial management
# human resource management
# information technology management
# marketing management
# operations management or production management
# strategic management
21st century
In the 21st century observers find it increasingly difficult to subdivide management into functional categories in this way. More and more processes simultaneously involve several categories. Instead, one tends to think in terms of the various processes, tasks, and objects subject to management.
Branches of management theory also exist relating to nonprofits and to government: such as public administration, public management, and educational management. Further, management programs related to civil-society organizations have also spawned programs in nonprofit management and social entrepreneurship.
Note that many of the assumptions made by management have come under attack from business-ethics viewpoints, critical management studies, and anti-corporate activism.
As one consequence, workplace democracy has become both more common and advocated to a greater extent, in some places distributing all management functions among workers, each of whom takes on a portion of the work. However, these models predate any current political issue, and may occur more naturally than does a command hierarchy. All management embraces to some degree a democratic principle—in that in the long term, the majority of workers must support management. Otherwise, they leave to find other work or go on strike. Despite the move toward workplace democracy, command-and-control organization structures remain commonplace as de facto organization structure. Indeed, the entrenched nature of command-and-control is evident in the way that recent layoffs have been conducted with management ranks affected far less than employees at the lower levels. In some cases, management has even rewarded itself with bonuses after laying off lower-level workers.
According to leadership academic Manfred F.R. Kets de Vries, a contemporary senior management team will almost inevitably have some personality disorders.
Topics
Basic functions
Management operates through five basic functions: planning, organizing, coordinating, commanding, and controlling.
Planning: Deciding what needs to happen in the future and generating plans for action.
Organizing: Making sure the human and nonhuman resources are put into place
Coordinating: Creating a structure through which an organization's goals can be accomplished.
Commanding: Determining what must be done in a situation and getting people to do it.
Controlling: Checking progress against plans.
Basic roles
Interpersonal: roles that involve coordination and interaction with employees
Informational: roles that involve handling, sharing, and analyzing information
Decision: roles that require decision-making
Managerial Skills
Political: used to build a power base and establish connections
Conceptual: used to analyze complex situations.
Interpersonal: used to communicate, motivate, mentor and delegate
Diagnostic: ability to visualize most appropriate response to a situation
Leadership: ability to lead and provide guidance to a specific group
Technical: Expertise in one's particular functional area.
Formation of the business policy
The mission of the business is the most obvious purpose—which may be, for example, to make soap.
The vision of the business reflects its aspirations and specifies its intended direction or future destination.
The objectives of the business refers to the ends or activity that is the goal of a certain task.
The business's policy is a guide that stipulates rules, regulations and objectives, and may be used in the managers' decision-making. It must be flexible and easily interpreted and understood by all employees.
The business's strategy refers to the coordinated plan of action it takes and resources it uses to realize its vision and long-term objectives. It is a guideline to managers, stipulating how they ought to allocate and use the factors of production to the business's advantage. Initially, it could help the managers decide on what type of business they want to form.
Implementation of policies and strategies
All policies and strategies must be discussed with all managerial personnel and staff.
Managers must understand where and how they can implement their policies and strategies.
A plan of action must be devised for each department.
Policies and strategies must be reviewed regularly.
Contingency plans must be devised in case the environment changes.
Top-level managers should carry out regular progress assessments.
The business requires team spirit and a good environment.
The missions, objectives, strengths and weaknesses of each department must be analyzed to determine their roles in achieving the business's mission.
The forecasting method develops a reliable picture of the business's future environment.
A planning unit must be created to ensure that all plans are consistent and that policies and strategies are aimed at achieving the same mission and objectives.
All policies must be discussed with all managerial personnel and staff that is required in the execution of any departmental policy.
Organizational change is strategically achieved through the implementation of the eight-step plan of action established by John P. Kotter: Increase urgency, get the vision right, communicate the buy-in, empower action, create short-term wins, don't let up, and make change stick.
Policies and strategies in the planning process
They give mid and lower-level managers a good idea of the future plans for each department in an organization.
A framework is created whereby plans and decisions are made.
Mid and lower-level management may add their own plans to the business's strategies.
Levels
Most organizations have three management levels: first-level, middle-level, and top-level managers. These managers are classified in a hierarchy of authority, and perform different tasks. In many organizations, the number of managers in every level resembles a pyramid. Each level is explained below in specifications of their different responsibilities and likely job titles.
Top-level management
The top consists of the board of directors, president, vice-president, CEOs and other members of the C-level executives. They are responsible for controlling and overseeing the entire organization. They set a tone at the top and develop strategic plans, company policies, and make decisions on the direction of the business. In addition, top-level managers play a significant role in the mobilization of outside resources and are accountable to the shareholders and general public.
The board of directors is typically primarily composed of non-executives which owe a fiduciary duty to shareholders and are not closely involved in the day-to-day activities of the organization, although this varies depending on the type, size and culture of the organization. These directors are theoretically liable for breaches of that duty and typically insured under directors and officers liability insurance. Fortune 500 directors are estimated to spend 4.4 hours per week on board duties, and median compensation was $212,512 in 2010. The board sets corporate strategy, makes major decisions such as major acquisitions, and hires, evaluates, and fires the top-level manager and the CEO typically hires other positions. However, board involvement in the hiring of other positions such as the Chief Financial Officer has increased. In 2013, a survey of over 160 CEOs and directors of public and private companies found that the top weaknesses of CEOs were "mentoring skills" and "board engagement", and 10% of companies never evaluated the CEO. The board may also have certain employees report to them or directly hire independent contractors; for example, the board typically selects the auditor.
Helpful skills of top management vary by the type of organization but typically include a broad understanding competition, world economies, and politics. In addition, the CEO is responsible for implementing and determining the broad policies of the organization. Executive management accomplishes the day-to-day details, including: instructions for preparation of department budgets, procedures, schedules; appointment of middle level executives such as department managers; coordination of departments; media and governmental relations; and shareholder communication.
Middle-level managers
Consist of general managers, branch managers and department managers. They are accountable to the top management for their department's function. They devote more time to organizational and directional functions. Their roles can be emphasized as executing organizational plans in conformance with the company's policies and the objectives of the top management, they define and discuss information and policies from top management to lower management, and most importantly they inspire and provide guidance to lower level managers towards better performance.
Middle management is the midway management of a categorized organization, being secondary to the senior management but above the deepest levels of operational members. An operational manager may be well-thought-out the middle management, or may be categorized as non-management operate, liable to the policy of the specific organization. Efficiency of the middle level is vital in any organization, since they bridge the gap between top level and bottom level staffs.
Their functions include:
Design and implement effective group and inter-group work and information systems.
Define and monitor group-level performance indicators.
Diagnose and resolve problems within and among work groups.
Design and implement reward systems that support cooperative behavior. They also make decision and share ideas with top managers.
Lower-level managers
Consist of supervisors, section leaders, foremen, etc. They focus on controlling and directing. They usually have the responsibility of assigning employees tasks, guiding and supervising employees on day-to-day activities, ensuring quality and quantity production, making recommendations, suggestions, and up channeling employee problems, etc. First-level managers are role models for employees that provide:
Basic supervision
Motivation
Career planning
Performance feedback
Training
Universities around the world, offer bachelor's and advanced degrees, diplomas and certificates in management, generally within their colleges of business and business schools but also in other related departments. There is also an increase in online management education and training in the form of electronic educational technology .
United States of America
At the graduate level students may choose to specialize in major subareas of management such as entrepreneurship, human resources, international business, organizational behavior, organizational theory, strategic management. accounting, corporate finance, entertainment, global management, healthcare management, investment management, Leaders in Sustainability and real estate
Current best practices
While management trends can change rapidly, the long term trend in management has been defined by a market embracing diversity and rising service industry. Managers are currently being trained to encourage greater equality for minorities and women in the workplace by offering increased flexibility in time worked, better retraining, and innovative performance markers. Managers destined for the service sector are being trained to use unique measurement techniques, better worker support and more charismatic leadership styles. Human resources finds itself increasingly working with management in a training capacity to help collect management data on the success of management actions with employees.
Tuesday, April 14, 2015
Here's how to solve the 'simple' high-school math problem stumping everyone on the internet
A question from a global math Olympiad for high-school children in Singapore is going viral after the question was leaked online.
The question seems simple — all you need to do is work out Cheryl's birthday, based on three statements and with just 10 possible dates to chose from — but the logic to solving it will really make your brain crinkle.
First, here's the question so you can have a go for yourself:
Facebook
Here's the question in plain text:
Albert and Bernard just became friends with Cheryl, and they want to know when her birthday is. Cheryl gives them a list of 10 possible dates: May 15, May 16, May 19, June 17, June 18, July 14, July 16, August 14, August 15, August 17.
Cheryl then tells Albert and Bernard separately the month and the day of her birthday, respectively.
Albert: I don’t know when Cheryl’s birthday is, but I know that Bernard does not know too.
Bernard: At first I don’t know when Cheryl’s birthday is, but I know now.
Albert: Then I also know when Cheryl’s birthday is.
So when is Cheryl’s birthday?
Think you know the answer? The question prompted so much confusion that the creators of the test posted an explanation on Facebook to clarify matters.
The official solution is below. However, some commenters have found the logic even more confusing than the question itself, so we've broken it down even further below.
If that solution confused you, we've broken it down piece by piece here:
- At the start, Albert and Bernard are each given one piece of information about Cheryl's birthday. Albert is given the month and Bernard is given the day. You have to assume that Cheryl was smart enough not give either of them a day or month that would enable them to work out the full date on their own.
- Now back to Bernard. Bernard knows the day (but not the month) the birthday falls on. We can rule out May 19 and June 18 straightaway because these days (18 and 19) occur only once in the list of dates. In contrast, 14, 15, 16, and 17 all appear twice. So, if Bernard was told either 18 or 19, he would be able to infer the month by knowing only the day. And that would be a different puzzle. So we can cross those two dates off the list.
Facebook- But Albert knows that Bernard does not initially know the birthday. How? Well, Albert knows the month it falls in. Had Cheryl told Albert May or June (the only two months with unique number dates) then it's possible (but not guaranteed) that Bernard already knows the full date. But Albert knows that Bernard doesn't know the full date, which means Cheryl must have told Albert that the month is either July or August. So all other months get crossed off the list.
Facebook- Bernard realises what the date is after Albert first says that he knowsthat Bernard doesn't know it. How does this work? Once Albert says that Bernard doesn't know, it shows to Bernard that it can't be in May or June. (After all, if it was, then Albert wouldn't know that Bernard doesn't know.) So this leaves July and August. Now, remember that Bernard knows the day (but not the month). Of the 5 options, 14 is the only one repeated twice. If it were July 14 or August 14 he still wouldn't know — but he does know, which means the day he was told must have been 15, 16, or 17, and we can cross another two possibilities out.
Facebook- And then, after Bernard realises what the date is, Albert follows suit. This is because — as we've established — Albert knows only the month. With 3 options left, if Albert had been told it were in August, he still wouldn't know, because there are 2 August options left. But that's not the case — Albertdoes know with certainty what date it is. From this we can infer that it isJuly 16, as there's only one July option there.
Facebook
To recap, Albert was told that Cheryl's birthday was in July, while Bernard was told it landed on the 17. This limited knowledge allowed each to narrow down their options — and by making inferences from the other's ignorance, the two could continue to thin down the possible categories until there was only one option left.
By now, many people have chimed in to offer their own way of solving this math elimination problem and even an alternative answer of August 17 — to which the Singapore and Asian School Math Olympiads has also responded.
"If there are two possible answers, then this problem is ambiguous," the organisation said in a Facebook post.
Still, there are others who are willing to find the humour in all of this. One commenter writes: "I personally know Cheryl and her birthday is May 19."
Sunday, April 12, 2015
7-S Framework McKinsey
Definition: 7-S Framework McKinsey
The McKinsey 7- S framework is a popular model used in organizations to analyse the environment to investigate if the company is achieving its intended objectives.
The name of the model can be explained by the fact that the model was developed by Tom Peters & Robert Waterman, consultants at the McKinsey & Company consulting firm.
The model proposes 7 interdependent factors – 3 hard ‘S’ i.e. strategy, structure, systems; and 4 soft ‘S’ i.e. shared values, skills, style and staff.
The hard ‘S’ are more tangible, easily to define and easy to influence than the soft ‘S’.
Strategy – It refers to the intended sequence of actions taken by a company to achieve its goals and objectives. It deals with resource allocation and includes competition, customers and the environment.
Structure – It refers to how the various business units are structured and how they communicate with each other. A company’s structure may be centralized or decentralized or may take many other forms depending on the company’s culture and values.
Systems – This includes a host of systems within an organization that define its processes and routines. It includes performance appraisal system, financial systems, IT systems etc.
Shared values – These are the core values of the company that connect all the other 6 factors. These are the fundamental ideas or guiding principles that lay the foundation of businesses.
Skills – These define the core competencies of the employees.
Style – This spans the core beliefs, norms and management style in the organization.
Staff – It refers to the number and type of employees in the organization. It is very important for an organization to manage its human capital to create competitive advantage.
Friday, April 3, 2015
Marketing: Brand Portfolio: Defination
Definition: Brand Portfolio
The brand portfolio of a company is the complete range of all brands and brand lines it offers for sale in a particular category or market segment. A brand portfolio is said to be optimal when each brand in it has the ability to maximize equity in combination with all the other brands.
The basic principle of a brand portfolio is to maximize market coverage and to offer enough brands so that no potential customers feel left out, but at the same time to minimize overlap so that no two brands cannibalize each other. A good brand portfolio is marked by the clear differentiation of the component brands ad economy (Marketing and production costs are justified by the size of the end customer segment).
Brand portfolios must be continuously pruned, so as to identify weak brands, reenergize them or to kill off the unprofitable ones.
Within a portfolio, brands can play the following roles:
• Flankers (or fighters): Positioned with respect to the competitors’ brands so that the flagship or more important brands are protected. Care should be taken so as not to cannibalize the flagship brand.
• Cash cows: these may be showing falling sales but still command decent profits despite less marketing support.
• Low-end entry level: Relatively low-priced brands designed to attract the first-time consumer to the brand franchise. These customers can later be “traded up’ to higher-priced brands.
• High-end prestige: Higher-priced brands to add prestige and credibility to the entire portfolio
Tuesday, March 31, 2015
TOP MBA JOB INTERVIEW QUESTIONS AND ANSWERS
Interviewing a candidate for a job is a tough task not only for the a candidate but also for the recruiter. Each one of them is at their best to prove their worth as a potential employee. Yet some cross the line and get selected to get the coveted job. Here are the basic questions you’re most likely to be asked in a job interview:
1) Question: Tell me about yourself and your background
Answer: The first question that a candidate is suppose to answer. The best way to tackle such a question is so quickly run the panel through your education, your achievements in academics, previous work experience (if you have worked before), exceptional feats, extra-curricular achievements etc. Such an explanation is a chronological manner gives a systematic approach to the interview
2) Question: Why have you applied for this position and job opening?
Answer: Recruiters need to see that you have a complete idea about the job decription and the skill sets required for the position you are applying for. Hence, they want to understand your knowledge about the profile and whether this job was your preference or not
3) Question: What knowledge do you have about our company?
Answer: Until and unless you are thorough about the company you are applying for, chances of selection are quite bleak. Remember, organisations are looking for skilled resources to build their company, each revenue and also select potential leaders who stay long in the organisation
4) Question: Why did you quit your last job? or Why are you still a fresher?
Answer: The reason behind you change of job is pivotal. The company wants to know whether you were an asset to you previous recruiter and that you are changing at your will for better avenues. However, if you have been forced to leave your previous job due to personal reasons or failing to meet company expectations, its gives a bad impression. Also, freshers are grilled as to why they haven't taken "efforts" to enhance their professional skill sets by taking up some job before completing higher studies.
5) Question: What job duties, responsibilities, initiatives etc have you taken?
Answer: This is a critical answer as far as the recruiter understanding your cohesion with the job profile being offered. Be short, crisp and confident in answering such a question. The best way is to break up the answer into three: (a) problem statement which you worked on; (b) your understanding, analysis, actions, execution (c) end result and how it benefited the company revenue or operations
6) Question: Tell me about your Strengths and Weaknesses
Answer: Most candidates don't understand the seriousness of this question but then this carries a lot of weightage as recruiters know that how well do candidates know themselves. Whatever strengths are described need to be backed up by some experience, else it appears to be only worthless statements. Weaknesses is a question which most people fail to tackle and end up saying 'I don't have weaknesses'. Every human being has some weak points whether they are lazy, lack certain skills, less attentive, over-emotional etc. Whatever the weaknesses are, mention that you are working to rectify them consciously.
7) Question: Give an example where you handled a team, managed a crisis etc
Answer: Such a question tells about the responsibilities and maturity levels that a candidate is able to handle. All the above questions are a part of an everyday life of a budding manager. Hence, real-life experiences of the candidate add more spine to the education and work-experience.
8) Question: Where do you see yourself 5 years from now?
Answer: This answer tells how ambitious and career-oriented the candidate is. A correct answer can show the career path the candidate wants to achieve by gradually growing at the companys' hierarchial pace. If you want to become an entrepreneur, then mention that but reiterate that for that you would want to gain atleast 3 to 5 years of professional work experience. This confidence shows that you are mentally prepared and respect you career choices as well.
9) Question: What salary range are you looking for?
Answer: The salary structure is the most important discussion that happens in the interview. A salary discussion is a positive sign but yet it is not affirmative. A candidate must quote a confident estimate that he or she feels must get, "as per the industry standards". However, one mustn't also under estimate and quote a lower salary, as it can backfire and can be alost opportunity at the beginning of the career.
Sunday, March 1, 2015
Key Management Models, Every Models of Business management explained
key management approaches is very useful books for every students, speciLly for BBA and MBA and for those whoa rewriting thesis:
To download click here
To download click here
Saturday, February 28, 2015
Full notes on extraction of copper and zinc
Extraction of Copper from Copper pyrite
The principle ore of copper is copper pyrite and copper is extracted from this ore. The different steps in extraction of copper are:
Crushing and Concentration:
The ore obtained from mines are broken down into small piece by jaw crusher and then pulverized. The ore being sulphide ore is concentrated by froth floatation process. Pulverized ore is kept in water containing pine oil and the mixture is agitated by passing compressed air. Ore forms froth with pine oil and comes to the surface and is skimmed off while impurities are left in water.
Roasting
The concentrated ore is heated in excess supply of air on the hearth of reberberatory furnace below its melting point. The different changes during roasting are:
a. Moisture and volatile impurities are driven out.
b. Non-metallic impurities like sulphur, phosphorous, arsenic etc. are removed as their oxides.
S + O2 → SO2
P4 + SO2 → 2P2O5
c. Copper pyrite dissociates into individual sulphide
2CuFeS2 + O2 → Cu2S + 2FeS + SO2 major r × n
Small amount of metal sulphides are oxidized to oxides.
2FeS + 3O2 → 2FeO + SO2 minor reaction
2Cu2S + 3O2 → 2CuO + 2SO2
Smelting
The roasted ore, coke and silica (flux) is charged a water jacketed blast furnace when hot air is passed into blast furnace. Fes if oxidized to FeO which combines with S1O2 to form ferrous silicate as slag.
2FeS + 3O2 → 2FeO + 2SO2
FeO + S1O2 → FeS1O3
Flux Ferrous Silicate
As long as Fes is present in the mixture Cu2O can’t be formed as copper has higher affinity for sulphur than oxygen. In molten state FeS & Cu2S are missible and the molten mixture of Cu2S and FeS is called copper malte. The lower end of blast furnace has two openings for slag and copper matte.
Fig: Blast Furnace for extraction of copper
Bassemerisation
The molten matte is mixed with little silica and charged into a Bessemer converter. Lined internally by basic lining of CaO or MgO. Hot air is blown into the mixture which converts remaining FeS. To FeSiO3.
2FeS + 3O2 → 2FeO + 2SO2
FeO + SiO2 → FeSiO3 (slag)
The slag is removed and air is passed. The air oxidized Cu2S partially to Cu2O which then reduces remaining Cu2S to metallic copper. During this process no external reducing agent is used so it is an example of self-reduction.
2CuS + 3O2 → 2Cu2O + 2SO2
2Cu2O + Cu2S → 6Cu + SO2
The reaction is highly exothermic and copper obtained is in molten state. During solidification, SO2 escapes forming blisters on the surface of metal. This variety of copper containing about 2% of impurity is blister copper.
Refining:
Blister copper consists of about 2% of impurities consisting of cliver, Glod, Zinc, Nicket etc. It is mostly purified by electrolytic method. A block of impure copper is anode, a strip of pure copper is cathode while solution of CuSO4 containing dil H2SO4 is e;ectrolyte. On passing current, impure copper dissolves and equivalent amount of pure copper is deposited at cathode. Impurities are collected below anode as anode mud.
CuSO4 (aq) → Cu++ + SO–4
At cathode: Cu++ + 2e → Cu
At anode: Cu → Cu++ + 2e
Physical Properties:
- It is a transition metal having characteristic red color.
- It is highly malleable & ductile and has high electrical and thermal conductivity
- It has high melting point 10830c and bpt 2320c
- It has specific gravity 8.93
Chemical properties
Action of air:
Dry air has no effect but moist air containing CO2gas forms a green layer of basic copper carbonate.
Cu + O2+ CO2 + H2O → CuCO3Cu(OH)2
Moist air basic copper carbonate
On heating in air 9000c, copper forms cupric oxide or black oxide of copper,
4Cu + O2 900 → 2CuO
Cupric oxide
On further heating above 11000c, copper gives cuprous oxide or red oxide of copper.
4Cu + O2 1000 → 2Cu2O
Cuprous oxide
Action of water:
Water has no effect on copper.
Action of Alkalis:
Alkalis has no effect on copper.
Action of Acids:
a) With HNO3
dil HNO3 does not react with copper while moderately conc. HNO3 (1:1) is reduced to Nitric oxide by copper.
3Cu + 8HNO3 → 3Cu (NO3)2 + 2NO + 4H2O
moderately conc.
Conc. HNO3 is reduced to Nitric oxide by copper.
Cu + 4HNO3 → Cu (NO3)2 + 2NO2 + 2H2O
Conc
b) With H2SO4 :
dil. H2SO4 alone does not react but hot dil. H2SO4 in presence of air gives CuSO4
2Cu + 2H2SO4 + O2 → 2CuSO4+2H2O
Hot & dil.
With hot and conc. H2So4, Coppe gives So2 gas.
Cu + 2H2SO4 → CuSO4 +SO2+2H2O
Hot & conc.
c) With HCl:-
Copper reacts with hot and conc HCl in presence of air forming cupric chloride.
2Cu+4HCl+ O2 → 2CuCl2+2H2O
5) Displacement reaction:-
Copper can displace metals lying below it in electrochemical series from their salt solution.
Cu+2AgNo3 → Cu (No3)2+2Ag
3Cu+2Aucl3 → 3Cucl2+2Au
Uses of Copper:-
i) It is in making electrical cables.
ii) It is used in making coins.
iii) It is used in making allays like brass, German Silver.
iv) It is Rold Gold, constantan, bell metal etc.
iv) It is used in making utensits.
v) It is used in making scientifi equipments like calioriemeter boilers .
Extraction of Zinc from Zinc Blende
Concentration:
Zinc blende is concentrated by floath floatation process. The pulverized ore is kept in large tank containing water and pine oil. The mixture is agitated by passing compressed air. Ore forms froth and comes to the surface while impurities are left in water.
Roasting:
The concentrated are is heated in excess supply of air above 9000c on the hearth of reberveratory furnace. During roasting. Zinc sulphide is converted to Zinc Oxide.
2ZnS + 3O2 → 2ZnO + 2SO2
Small amount of ZnS may be oxidized to ZnSO4 but above 9000c , ZnSO4 decompose forming Zinc Oxide (ZnO)
ZnS + 2O2 → ZnSO4
ZnSO4 above 900 → 2ZnO + 2SO2 + O2
Reduction (Smelting):-
ZnO obtained during roasting is mixed with coke and heated strongly where ZnO is reduced to Zn by carbon.
ZnO + C → Zn + CO
The reduction is done in vertical refort. In this process roasted are mixed with coke in the ration of 2:1 and small briquets are made. These briquets are fed into vertical report furnance, from the charging door. The report is heated externally by burning produce gas (w+N2) to about 14000c. The vapour of zn is camed to condenser where it condenses to give molten zinc called spelter zinc.
Purification:-
Zinc spelter contains pb, fb, cd, as, etc. as impurities. Impure zinc can be purified by following methods.
a. By fractional distillation:-
The bpt of Pb, Fb are higher than that of zinc while that of cadmium, arsenic are lower than that of zinc. When distillation is carried out around 1000°c, zinc, Cd, As, etc. distill off leaving Pb and Fe the distillate is then heated to 800°c where cd and as distill off leaving pure zinc. This sample of Zn is about 99% pure.
b. By electrolysis:-
Zinc of higher purity can be obtained by electrolysis. Pure zinc rod is used as cathode while a block of impure zinc is used as anode. A mixture of ZnSO4 and dill H2SO4 is used as electrolyte. On passing current impure zinc dissolves and equivalent amount of pure zinc is deposited at cathode.
Physical Properties
i. It is a blueish white lusticous metal.
ii. zinc is brittle at ordinary temperature but it becomes malleable from 100-150. c then again it become brittle.
iii. It melts at 420. c and boils at 900. c and has sp. Gravity 7.13.
Chemical Properties
1. Action of air:-
Dry air has effect on zinc but in moist air, zinc forms a protective layer of basic zinc carbonate.
Zn + O2 + H2O + CO2 → ZnCO3.Zn (OH)2
When heated in air, zinc burns greenish blue flame forming clouds of light, white power of zinc oxide which is commonly known as ‘philosopher’s wool. Beside this name, other common names are ‘Zinc white and china white.
2Zn + O2 → 2ZnO
2. Action of water:-
Pure zinc does not react with water but impure zinc displaces hydrogen gas. Zn-inc reacts with hno3 in four different concentrations giving different reduced product.
Zn + H2O → ZnO + H2
3. Action with acids:
Dilute H2SO4 and dil. HCl gives H2 gas with zinc
Zn + dil. H2SO4 → ZnCl2 + H2
Zn + dil. HCl → ZnSO4 + H2
With hot and conc. H2SO4 zinc gives SO2 gas
Zn + 2H2SO4 → ZnSO4 + SO2 + 2H2O
Zinc reacts with HNO3 in four different conditions giving different product:
i. with very dil. HNO3
With very dil. HNO3, Zn gives ammonium nitrate
4Zn + 10HNO3 → 4Zn(NO3)2 + NH4NO2 +3H2O
ii. with dil. HNO3
Zinc reduces dil. HNO3 to nitrous oxide (N2O)
4Zn + 10HNO3 → 4Zn(NO3)2 + N2O +5H2O
iii. With modrately conc. HNO3
Zinc reduces moderately conc. HNO3 to NO (nitric oxide)
3Zn + 8HNO3 → 3Zn(NO3)2 + 2NO2 +4H2O
iv. With conc. HNO3
Zinc reduces conc. HNO3 to NO2 (nitrogen dioxide)
Zn + 4HNO3 → Zn(NO3)2 +2 NO2 +2H2O
4. Reaction with Alkalies:-
Zinc readily dissolve in hot and conc. solution of caustic bases like NaOH , KOH, etc giving hydrogen gas.
Zn + NaOH → Na2ZnO2 + H2
Zn + KOH → K2ZnO2 + H2
5. Displacement Reaction:-
Zinc can displace less electropositive metals from their salt solution
Zn + CuSO4 → ZnSO4 + Cu
Zn + 2Na[Au(CN)2] → NA2[Zn(CN)4] + 2Au
Uses of zinc:
- It is used for galvanization of iron.
- It is used in making alloys like Brass. German metal, German silver, etc
Galvanization
The process of applying a coat of zinc on base metal like iron is galvanization Iron is galvanized to protect iron from resting the galvanization is done in following steps.
i. cleaning and picking:
Before applying zinc coat on iron, the surface of iron should be clean. The cleaning is done first by sand blast and then washed by dipping in diluted acid. The process of cleaning iron by using dil. acid is called picking.
ii. Applying of zinc coat:
The coat of zinc can be applied on iron surface by 3 methods.
a. By electroplating:-
Zinc can be electroplated on iron by keeping iron article as cathode, zinc as anode and znso4 solution as electrolyte. On passing current a layer of zinc is coated on iron article.
b. By metallizing :-
Zinc can be directly applied by dipping iron article in molten zinc this process is generally used for galvanization of iron sheets. Iron sheets are dipped in molten zinc bath & then passed through huge rollers that distributer zinc coat equally.
c. By sherardizing:-
The process is used for galvanization of small iron articles like nail, screws etc. In this process iron article are mixed with zinc dust and then heated in enclosed vessel for few hours when coat of zinc is applied on iron.
· It is used in making amalgam.
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