Advertisements
Advertisements
Question
Give the uses of zinc.
Advertisements
Solution
- Metallic zinc is used in galvanising metals such as iron and steel structures to protect them from rusting and corrosion.
- Zinc is also used to produce die-castings in the automobile, electrical and hardware industries.
- Zinc oxide is used in the manufacture of many products such as paints, rubber, cosmetics, pharmaceuticals, plastics, inks, batteries, textiles arid electrical equipment. Zinc sulphide is used in making luminous paints, fluorescent lights and x-ray screens.
- Brass an alloy of zinc is used in water valves and communication equipment as it is highly resistant to corrosion.
RELATED QUESTIONS
Write the names and chemical formulae of any one ore of iron.
Write the reactions involved in the zone of reduction in blast furnace during extraction of iron.
Mention names and formulae of two ores of alumunium.
What is the role of CO in the extraction of Iron?
Indicate the principle behind the method used for the refining of zinc.
What is the role of silica in the extraction of copper?
Which form of the iron is the purest form of commercial iron?
Which of the ores mentioned can be concentrated by magnetic separation method?
Define leaching.
Write the names and chemical formulae of any ‘two’ minerals of aluminium.
Explain the following methods to protect metals from corrosion:
Galvanization
Copper has the face centred cubic structure. The coordination number of each ion is:
How will you convert the following:
[Ag(CN)2]− to Ag
Which of the following options are correct?
(i) Cast iron is obtained by remelting pig iron with scrap iron and coke using hot air blast.
(ii) In extraction of silver, silver is extracted as cationic complex.
(iii) Nickel is purified by zone refining.
(iv) Zr and Ti are purified by van Arkel method.
In the extraction of aluminium by Hall-Heroult process, purified \[\ce{Al2O3}\] is mixed with \[\ce{CaF2}\] to:
(i) lower the melting point of \[\ce{Al2O3}\].
(ii) increase the conductivity of molten mixture.
(iii) reduce \[\ce{Al^{3+}}\] into \[\ce{Al(s)}\].
(iv) acts as catalyst.
Which of the following reactions occur during calcination?
(i) \[\ce{CaCo3 -> CaO + CO2}\]
(ii) \[\ce{2FeS2 + 11/2 O2 -> Fe2O3 + 4SO2}\]
(iii) \[\ce{Al2O3. {x}H2O -> Al2O3 + {x}H2O}\]
(iv) \[\ce{ZnS + 3/2 O2 -> ZnO + SO2}\]
In the electrolytic process for the extraction of aluminium the electrolyte is:-
When compared to ΔG° for the formation of Al2O3 ΔG° for the formation of Cr2O3 is
Match List I with List II.
| List - I | List - II | ||
| a. | Siderite | I. | FeCO3 |
| b. | Malachite | II. | CuCO3 · Cu(OH)2 |
| c. | Sphalerite | III. | ZnS |
| d. | Calamine | IV. | ZnCO3 |
Choose the correct answer from the option given below.
Match List - I with List - II.
| List - I | List - II | ||
| (One) | (Composition) | ||
| (A) | Siderite | (I) | FeCO3 |
| (B) | Malachite | (II) | CuCO3 · Cu(OH)2 |
| (C) | Sphalerite | (III) | ZnS |
| (D) | Calamine | (IV) | ZnCO3 |
Choose the correct answer from the options given below:
