Introduction to Metallurgy

Q. What is meant by refining of metals? Name the three common methods used for refining.

Q.

Why does the concentration of the electrolyte remain constant during electroplating?

Q. What is an alloy? Give three reasons why alloys are made.

Q.

Metals are refined by using different methods. Which of the following metals are refined by electrolytic refining?

(i) Au

(ii) Cu

(iii) Na

(iv) K

1. (i) and (ii)

2. (i) and (iii)

3. (ii) and (iii)

4. (iii) and (iv)

Q.

Define the term 'metallurgy'. State the processes involved in metallurgy.

Q.

What is Ag in chemistry?

Q.

All metals are solid at room temperature.

1. True

2. False

Q.

For the electrorefining of copper, what is the cathode made up of?

Q. Steel is made from a combination of:

1. Iron and Nickel
2. Iron and Cobalt
3. Iron and Carbon
4. Iron and Zinc

Q. Calcium, copper, lead, aluminium, zinc, chromium, magnesium, iron.
Choose the major metals from the list given above to make the following alloys:
(a) stainless steel
(b) brass.

Q. Which one of the following is not true of metals:
(a) Metals are good conductors of electricity.
(b) Metals are malleable and ductile.
(c) Metals form non-polar covalent compounds.
(d) Metal will have 1 or 2 or 3 electrons in their valence shell.

Q. Ammonium salts decompose on heating. What other property do ammonium salts have in common?

Q.

Compare and contrast the metallic character and hardness of sodium and iron. Justify.

Q. Which of the following metals can be refined by liquation?

1. Lead
2. Zinc
3. Iron
4. Sodium

Q. Highly reactive metals like sodium and potassium are extracted from their ore by the process of:

1. roasting
2. calcination
3. reduction of metal oxide
4. electrolytic reduction

Q. what are differences between metals and non-metals based on their cghemical properties

Q.

Select the correct answer from the list given in brackets.
An aqueous electrolyte consist of the ions mentioned in the list, the ion which could be discharged most readily during electrolysis $({\mathrm{Fe}}^{2+},{\mathrm{Cu}}^{2+},{\mathrm{Pb}}^{2+},{\mathrm{H}}^{+}).$.

Q. List 1 contains the metals/alloys (1, 2, 3, 4, 5) and list 2 contains their uses (A, B, C, D, E).

List 1 Metal/Alloy	List 2 Uses
1. aluminium 2. lead 3. brass 4. iron 5. zinc	A. steel making B. aeroplane wings C. galvanizing D. radiation shield E. electrical fittings

Copy and complete the following table write down the correct letter against the numbers representing metals.
An answer may be used only once.
The first has been done for you.

Metal	1	2	3	4	5
Use	B

Q. Why reactive metals are not extracted from their aqueous salt solutions by electrolysis? (2 marks)

Q.

Hydrogen is metal or nonmetal?

Q. What is an alloy? An alloy usually has some property which makes it useful in a specific way. What is the special property of:
(a) duralumin?
(b) type metal?

Q. Explain the terms:
(i) Electrorefining
(ii) Electrometallurgy
(iii) Anode mud

Q.

Which of the following elements can form alloys?

1. Nitrogen

2. Oxygen

3. Iron

4. Nickel

Q. Aluminium reacts with caustic soda to form :

1. Aluminium oxide
2. Sodium meta aluminate
3. Sodium tetra aluminate
4. Alumining hydroxide

Q.

State the composition and two uses of the following alloy.

(d) Bronze

Q. During the electrorefining of copper, the insoluble impurities that get settled down at the bottom of the anode are called an:

1. anode dirt
2. anode scum
3. anode mud

Q. Which of the following metals melt at room temperature?

1. Caesium
2. Bromine
3. Sodium
4. Gallium

Q. A student categorised the different elements as shown below :

	Characteristic	Al	S	Fe
a	Hardness	Yes	No	No
b	Malleability	No	No	Yes
c	Ductility	No	Yes	No
d	Conductor of electricity	Yes	No	Yes

Identify which of the given characteristics is not correctly matched with the corresponding element.

1. b and d
2. a, c, and d
3. c and d
4. a, b, and c

Q. In electrorefining of copper, some gold is deposited as:

1. Flux
2. Cathode mud
3. Anode mud
4. Slag

Q. The chemical formula of bauxite ore is ______.