This set of Engineering Chemistry Multiple Choice Questions & Answers (MCQs) focuses on “Applications of Electroplating”.
1. What is the main principle of electroplating?
Explanation: Electroplating is the process by which a metal gets deposited over the other in the presence of a metal salt (in aqueous solution). In this process, the water molecule is given out as the end product. Hence the principle behind electroplating is hydrolysis.
2. Which of the following is not an application of electroplating?
a) Decorative purposes
b) Coating of metal
c) Metal protection
d) Corrosion prevention
Explanation: Electroplating is the process by which a metal gets deposited over the other in the presence of a metal salt (in aqueous solution). Hence it is used in decorative purposes, in coating other metals etc. It does not help in preventing corrosion (painting helps in preventing corrosion).
3. The process of modifying a metal’s properties is called _________________
b) Electro deposition
c) Electro less plating
Explanation: Electroplating coats a thin layer of metal over the other metals but does not modify its properties. But electro deposition is the process by which the coating is permanent and the property of the coated metal changes.
4. What is a nickel strike?
a) Nickel deposition
b) Nickel coating
c) Nickel Plating
d) Nickel melting
Explanation: A strike layer, (also known as a flash layer), adhere a thin layer of high-quality nickel plating to the base material (parent material). Once up to 0.1 millimeters of nickel coats the product, a lower quality current density is used to improve the speed of product completion towards electron deposition.
5. Saucepans can be prepared through electrolysis of __________________
b) Galvanized zinc
Explanation: In the manufacture of saucepan, a thin layer of copper is made as anode and a thick layer of copper is made of anode. Suitable metal to be coated is placed as metal salt solution and the normal method of electrolysis is carried out.
7. Electroplating of chromium helps in preparing of ____________________
a) Car bumpers
Explanation: In the manufacture of bumpers a thin layer of chromium is made as anode and a thick layer of chromium is made of anode. Suitable metal to be coated is placed as metal salt solution and the normal method of electrolysis is carried out.
8. Reactivity series of metals is called as the __________________________
a) Preferential series
b) Electrochemical series
c) Electrolytic series
d) Selective discharge series
Explanation: According to law of electrolysis, displacement series (ascending order of displacement capacity of different metals) is called electrolytic series. The reactivity series is hence called electrochemical series (ability to react more).
9. What happens if molten Lead Bromide (PbBr2) is electrolyzed?
a) At anode, brown fumes of bromide gas are given off
b) At anode, molten lead can be seen
c) At cathode, brown fumes can be seen
d) At cathode, lead bromide can be seen
Explanation: When molten lead bromide is electrolyzed, we get impurities on the cathode region and pure metal on the anode side. Also during deposition (due to high initial ignition), molten lead gets formed on the anode side.
10. Discharge difficulty is highest in _____________________
a) Calcium ions
b) Copper ions
c) Lead ions
d) Silver ions
Explanation: Since calcium is considered to be a heavy metal, usually discharge in the electrolysis of calcium far tedious as compared to other metals. (in the discharge scale, calcium has the highest discharge ability).
Sanfoundry Global Education & Learning Series – Engineering Chemistry.
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