Roasting is generally carried out in case of :

1. Oxide ores

2. Sulphide ores

3. Silicate ores

4. Carbonate ores

Which substance is used as basic refractory material in furnace?

1. Al₂O₃

2. SiO₂

3. CaO

4. Fe₂O₃

Plumbo-solvency refers to:

1. oxidation of lead to lead oxide

2. oxidation of lead to red lead

3. dissolution of lead in water containing air

4. making lead wires by forcing heated metal through a die

Rutile is an ore of:

1. Ti

2. Zr

3. Mn

4. V

Which is not a mineral?

1. Mica

2. Peat

3. Quartz

4. Felspar

Which element is purified by Zone refining?

1. Ge

2. Ge and Si

3. Si

4. None

Alloy is an example of:

1. gel

2. aerosol

3. solid sol

4. emulsion

The second most common element on the earth is:

1. silicon

2. hydrogen

3. nitrogen

4. oxygen

Coating of zinc on iron objects is commonly known as:

1. electroplating

2. surface coating

4. galvanising

4. sheardising

Nickel is purified by thermal decomposition of its:

1. Hydride

2. Chloride

3. Azide

4. Carbonyl