Full notes on extraction of copper and zinc

Extraction of Copper from Copper pyrite

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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

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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.

Economic XI HSEB All Notes

All Notes on Economic Class XI
Statatstic
Nature of Economics
Basic Issue of Economics
Nepalese Economics
Numericals
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EFFECT OF CELEBRITY ENDORSEMENT ON CONSUMER BEHAVIOUR

The buying process which any consumer goes through before making a purchase can be broadly classified into two categories- thought situations and feel situations. Whereas in the first case, consumers process information and arrive at outcomes using facts and logic, in the second case, he tends to reach a decision based on his subjective likes or dislikes. As per the Elaboration Likelihood model, for the first scenario, marketers follow the central route to persuasion and the buying process is said to be a high involvement one. For the second scenario, peripheral routes of persuasion are used and the process is characterized as a low involvement one.

Figure 1

According to the FCB Grid developed by Richard Vaughn in 1980, for high involvement purchases, a consumer typically feels/ learns about the product first and then buys it. While for low involvement items, the ‘do’ portion precedes the learning/ feeling.

Figure 2

Motivation for the study

The variation in the hierarchies of effects for these two categories has a lot of relevance for a marketer since it gives him direction on how to best portray his offering to the consumer so that he purchases it. Using an endorser to promote the product has been a tried and tested formula for many companies. Through a number of studies it has been established that endorsers in an advertisement influence the buying behaviour of a consumer. (Biswas, Biswas and Das, 2006) Many studies have also been conducted to demonstrate the influence of endorsers on various marketing variables such as attitude towards product, purchase intention etc. (Petty, Cacioppo, & Schumann, 1983; Block & Atkin, 1983)

The aim of this paper would be to analyze and compare the effect of celebrity and expert endorsers on high and low involvement products to see whether it is different for the two product classes.

Experimental Methodology

For a high involvement purchase, a mobile phone was taken as the experimental product, while a biscuit packet was taken as a low involvement purchase. For each of these two products, two print ads of a fictional brand was designed, one endorsed by a celebrity and the other by an expert, were shown to two sets of 30 respondents each. Care was taken to ensure that the two groups were heterogeneous within but homogeneous across. Both the ads had the same celebrity endorsing the product, mobile in one, biscuit in the other. The 120 respondents rated the ads on the parameter of Claim Believability, the scale for which was adapted from Beltramini and Evans (1985). It is a 10 item 7 point Likert scale. The scale item is listed below.

Figure 3

The parameters in red were reverse coded to ensure that respondents do not blindly mark all the questions.

Initial Hypothesis

Obermiller and Spangenberg (2005) examined the relationship between ad skepticism and informational versus emotional appeal. Their studies showed that high skeptics are less responsive to emotional appeals. This result was consistent with Friestad and Wright (1994) who proposed that emotional appeals are developed by marketers specifically to circumvent consumers’ skeptical resistance to informational arguments. In a related study, Lord and Putrevu (2009) concluded that for products appealing to informational motivations, (high involvement) credibility was influenced by the expertise of the endorser while for products appealing to transformational motivations, attractiveness of the endorser has maximum impact on credibility.

Based on these studies, the following hypothesis was developed.

H1: Celebrity endorsement has a more positive effect on Claim believability of a low involvement product compared to a high involvement one.

H2: Expert endorsement has a more positive effect on Claim believability of a high involvement product compared to a low involvement one.

The posters of the four advertisements shown to the students are given below. The 1st one was for a High Involvement product- Smart Phone while the other was for a Low involvement one- glucose biscuit. Both ads had the exact same layout and colour scheme, with only the content differing in each. The celebrity chosen was also same for both the sets. This was done to remove any bias created due to the quality of the ad. For the brands, fictional names were chosen so as to eliminate pre-conceived notions in the minds of the respondents.

Figure 4
Expected Outcome

Since it is theorized that celebrities appeal more to the emotional senses, it is expected that the claim believability of consumers will be more for the low involvement product. For a high involvement product, a consumer is typically expected to gather further information before deciding to buy.

Experiment Results

The responses to the questionnaire were tabulated.. The mean scores for each of the parameters were calculated to arrive at the final rating given by the respondents to the ad. Refer to the excel sheet attached for further details.

It was observed that the mean score for the High Involvement product, mobile phone was 5.64 while that for the low involvement (biscuit) was 3.53. This showed that contrary to our initial hypothesis, claim believability of consumers was more for the mobile than the biscuit.

Statistical Analysis

H1: Celebrity endorsement has a more positive effect on Claim believability of a low involvement product compared to a high involvement one.

The ANOVA test for the dependent variable ‘Endorser’ with respect to the independent variable ‘Claim Believability’ for Celebrities showed the following result.

Figure 5

Given that the mean of claim believability for the consumers who were shown the print ad of the high involvement product, mobile, is considerably higher, and the difference in means is statistically significant, celebrity endorsement considerably increase the believability for the high involvement product

H2: Expert endorsement has a more positive effect on Claim believability of a high involvement product compared to a low involvement one.

The ANOVA test for the dependent variable ‘Endorser’ with respect to the independent variable ‘Claim Believability’ for Experts showed the following result.

Figure 6

Conclusion

This research experiment showed that experts have the highest influence in brand promotions of low involvement products. As the consumers have not invested their time to research about the product, expert opinion reinforces the consumer belief in the product and brand leading to higher claim believability.

However in case of high involvement products, celebrity endorsers are highly valued. Their impact on the brand promotions is more because consumers have invested sufficient time and have taken opinion from experts already. Celebrity endorsers help them achieve the aspirational value of owning that product. Thus the claim believability is more.

References

1.Ahmed, Azmat, & Farooq. (2012). Effect of celebrity endorsement on customer's buying behavior; A perspective from Pakistan. Interdisciplinary Journal of Contemporary Research in Business, 4(5), 584-592.

2.Biswas, Biswas, & Das. (2006). The differential effects of celebrity and expert endorsements on consumer risk perceptions. Journal of Adveritsing, 35(2), 17-31.

3.Block, & Atkin. (1983). Effectiveness of Celebrity Endorsers. Journal of Advertising Research, 23(1), 57-61

4.Petty, Cacioppo, & Schumann. (1983). Central and Peripheral Routes to Advertising Effectiveness: The Moderating Role of Involvement. Journal of Consumer Research, 10(2), 135-146.
5. Pooja Punjabi (2014) ,IIM Kozhikode, MBASkool.com

E-COMMERCE - THREAT TO TRADITIONAL RETAIL?

E-COMMERCE - THREAT TO TRADITIONAL RETAIL?

E-retail with its innovative business model is radically changing the way people traditionally shop. The demise of companies like Tower Records, Borders can be attributed to growing acceptance of e-retail. The extremely high growth rates are a cause of concern for traditional retail. However, despite glaring advantages, e-retail is only 5% of total retail sales. Traditional stores have inherent advantages in terms of experiential products and a huge supporting ecosystem. But, the market dynamics are changing and traditional stores can’t rely on the momentum barrier to keep out e-retail. The future lies in innovation and the ability to integrate channels to satisfy evolving customer needs.

Emergence of e-retail: How real is the threat for traditional retailers?

Ever since the launch of Amazon and eBay in 1995, E-Commerce has been periodically touted as the next big disruption with the power to drive traditional retail stores to extinction. Tower Records, a retail music chain went bankrupt in 2006. Musicland was sold in 2006. Borders, a bookstore went bankrupt in 2011. The common thread through all these failures is innovation pioneered through e-retailing by companies like Amazon, the Apple Store and Napster. A look at the growth rates in the past 5 years will indicate that we may possibly be headed in that direction. The growth in traditional retail has been 3.3% year on year compared to e-retail’s growth of 17.7% in the same time period.

A look at the overall market statistics, however, reveals a different story. E-retail, although it has been around for more than 2 decades, accounts for a mere 4.59% of total retail sales in the world. This inconsistency between the hype about e-retail and the actual adoption warrants a deeper understanding of the two channels which can also serve as a pointer to the future prospects of traditional and e-retail stores.

The effect of product category on consumer’s choice of retail channel

The consumer acceptance of e-retailing depends on product category, value addition by the seller and engagement required in the buying process. For high value purchases in categories like consumer electronics and consumer appliances, e-retailing has captured approximately 13% and 10%, respectively, of the total sales. The customers often resort to “showrooming” for these categories; experiencing the product in offline stores and then buying it online at lower prices. For experiential products like beauty and healthcare, a majority of the consumers still prefer offline stores but are turning online for repeat purchases for better prices.

Media products like music, movies and books where the physical store adds little value derive a sizeable portion of their overall sales from the online channel.

Online sales of apparel and footwear, primarily experiential purchases, has grown at a much faster rate than offline sales and accounts for approximately 7% of the total sales. One of the major reasons for this is free shipping and returns in e-retailing allowing customers to check fits and sizes.

What “clicks” for e-retail?

Traditionally, the distance between the customers and the retailers was an important determinant on the selection of the retailer and travelling entailed significant costs. With e-retail, physical distance has become almost irrelevant, except to the extent of shipping charges which are mostly waived off. It has also eliminated the problem of information asymmetry between the sellers and buyers with elaborate product information including price comparison across all available sellers, user reviews and opinion blogs.

The product range is a significant competitive advantage for the online stores as the physical stores have limitations on the product range that they can carry due to expensive retail space. The online stores, on the other hand, carry inventory in warehouses or function as intermediaries between buyers and sellers (marketplace model).

The asset light model of the online stores brings significant cost advantages which are passed to the consumers in the form of discounts and special deals. This has attracted price sensitive buyers. For many people, shopping is a necessary evil and the convenience provided by e-retail in terms of time, fuel and effort savings is alluring.

The experience of traditional retail

On the other hand, for many buyers, shopping is a rejuvenating and fulfilling experience which provides instant gratification. One of the major shortfalls of e-retail and strengths of traditional retail is the personal touch or interactive experience. Customer service or in-store assistance is still valued by these customers who are willing to pay a little extra for their purchases.

For most people, the ability to touch feel, try and test the products also contributes to the superior experience of traditional stores. This is one of the major sustainable advantages in favour of traditional retailers which can’t be mimicked by the online retailers without significant increase in costs which would blunt their competitive edge in terms of pricing.

Due to the lag between order and delivery for online purchases, traditional retail stores have a service advantage with respect to the immediate, necessary and emergency requirements of the customer.

Barriers to e-retailing:

One of the most significant barriers facing e-retailers today is the momentum barrier. 95% of total retail sales are still offline and it is going to take a substantial amount of time before e-retail is widely adopted.

One of the other major barriers to e-retail is the ecosystem barrier. With 60% of the population without internet and out of reach of the e-retailers, there is a long time before e-retail can be a realistic threat to the traditional retailers.

For e-retail to grow beyond customer segments who value price, convenience and product information, it has to recreate the experience of the offline stores with a high level of customer service, speedy delivery. Replicating the experience and reducing delivery time through try and buy, free returns, more number of facilities will entail significant costs which will erode the price advantage of e-retail. This business model barrier will need to be tackled for further growth.

What does the future hold?

It will be difficult to sustain customers with singular strategies in the future. Offline customers may gradually experience dissatisfaction due to higher prices. Online customers may gradually detest the disengaged shopping experience. Omnichannel retailing or integration of offline and online channels to provide customers the convenience of e-retail and personal touch of offline stores at competitive prices through economies of scale and wider reach with lesser investment would be an answer to customer needs of price, experience and information. Tesco is a successful example of omnichannel retailing. It installed digital screens in Seoul subway stations for ordering groceries and staples. Customers ordered through those screens and picked up their order through stores. This enabled Tesco to increase its online sales by 130%.

Currently, e-retail occupies a small proportion of total retail and must overcome significant barriers before it can become a real threat to traditional retail. However, it is definitely altering the stakes of the game, ensuring that pureplay strategies either in e-retail or traditional retail stores will have limited success potential.

References:

1.Wessel M., & Christensen C.M. (2012, December). Surviving Disruption. Harvard Business Review. Retrived from https://hbr.org/2012/12/surviving-disruption

2.Rigby D. (2011, December). The Future of Shopping. Harvard Business Review. Retrieved from https://hbr.org/2011/12/the-future-of-shopping

3.Agarwal D. (2014, October 16). Is e-commerce a threat to traditional retail?. Retailer. Retrieved from http://www.indianretailer.com/article/technology/ecommerce/Is-e-commerce-a-threat-to-traditional-retail-2481/

4.Ecommerce Sales Growth vs Total Sales Growth Worldwide, by Product Category, 2013 (n.d). Retrieved from http://www.dotcomweavers.com/wpcontent/uploads/2014/03/dotcomweavers-5.gif

5.The Rapid Rise of Digital Music (n.d). Retrieved from http://mashable.com/2014/03/19/digital-music-chart/
6. Devam Sardana(2014) , IIM Ahmedabad MBASkool.com,

What is Product Concept?

Definition: Product Concept

Before marketing any product marketers study the product concept to give the best product to the customer. It says that consumers will prefer a product which is high on quality, performance and features against a normal product.

Innovation helps to get new product concepts

Example: - Apple is one company which works highly on product concept to get the best products to their consumers.

What is selling concept?

The selling concept essentially mirrors the thought that consumers will not purchase enough of the company’s products unless large-scale promotional and selling efforts are carried out by it.

This concept is used for goods which customers don’t buy normally, unsought goods like insurance etc. These goods are aggressively sold by tracking down the target segment and sold on the virtue of the product benefits.

The focus here is more on selling the products of the company to consumers without comprehending the market needs and increasing sales transactions rather than building and enhancing relationships with customers.

This concept works under poor assumptions that if customers are coaxed into buying a product then they will necessarily like it. Even if they don’t like it, they’ll forget their dissatisfaction over a period of time and buy the product again later.