Chemistry · Science General

Metallurgical Processes

1,403 Questions

This section explores key metallurgical processes including ore concentration, pyrometallurgy, and metal refining. It also covers corrosion and the properties of refractory materials. These chemistry questions are relevant for engineering and science entrance tests.

Pyrometallurgy furnacesMetal refining techniquesCorrosion protection methodsOre concentrationAuto reduction process

Metallurgical Processes Questions

Multiple choice

Identify the incorrect statement(s).

  1. In floatation process, ZnO and SO3 are formed from sulphide ores.
  2. To prevent corrosion of Zn, Fe is used as coating material.
  3. Cd metal is used in nuclear reactors as neutron excitation material.
  4. Mercury is used extensively in the production of sodium hydroxide and chlorine gas commercially.

  1. 1 and 2

  2. 2 and 3

  3. 3 and 4

  4. 1, 2, 3

  5. 2, 3, 4
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  1. The floatation process is the concentration method of sulphide ores. Zinc ores mainly ZnS are concentrated by floatation method, then roasted in air to give ZnO and SO2.
    1. Zn is used extensively for coating for the appliances made up of corrosive metals like Fe to prevent them from rusting.
    2. Cd metal absorbs neutrons very well, and is used to make control rods in nuclear reactors.
    3. The largest use of mercury is in electrolytic cells for the production of sodium hydroxide and chlorine gas at commercial level.
Multiple choice

By which of the following process purification of Al is done?

  1. Hoop’s process

  2. Wet process

  3. Van-Arkel process

  4. Mond process

  5. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This option is correct, because this process is for electrolytic refining of Al. The electrolytic cell consists of three liquid layers of different gravities. The top layer of pure Al acts as cathode. The bottom layer; molten impure Al acts as anode. The middle layer is fused cryolite and barium fluoride. It acts as an electrolyte. When current flows, Al ions from the middle layer are discharged at the cathode.

Multiple choice

Alloy steel containing chromium, to resist rusting is known as _____.

  1. wrought iron

  2. cast iron

  3. hard steel

  4. stainless steel

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Stainless steel is an alloy of iron containing chromium, which creates a thin, protective layer of oxide on the surface. This layer prevents the iron from reacting with oxygen and water, thereby resisting rust and corrosion.

Multiple choice

Chrome steel is used to make ____.

  1. springs tools

  2. aircrafts

  3. axle of motor cars

  4. engine parts

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Chrome steel is known for its hardness and high tensile strength, which are essential for manufacturing durable tools and springs. While it is used in automotive parts, it is specifically valued for its resilience in tool making.

Multiple choice

Which of the following statement(s) is/are false?

P. Boron and Gallium form BF63- ions. Q. Alclad is the alloy of aluminium used in the formation of corrosion resistant sheet. R. Boron fibres are used in making bullet-proof vest and light composite material for aircraft.

  1. P only

  2. Q only

  3. R only

  4. P and Q

  5. Q and R
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

P. Due to non-availability of d orbitals, boron is unable to expand its octet. Therefore, the maximum covalence of boron cannot exceed 4. Al, Ga, In and Tl have vacant d orbitals and form such type of ions. Q. Alclad is a trademark of Alcoa used as a generic term to describe corrosion-resistant aluminium sheet formed from high-purity aluminium surface layers metallurgically bonded to high-strength aluminium alloy core material. R. Boron fiber exhibits a unique combination of high strength, high modulus and large diameter. Boron fibres are used in making bullet-proof vest and light composite material for aircraft.

Multiple choice

Rusting of iron takes place due to

  1. oxidation

  2. carbonation

  3. exidiation

  4. corrosion
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Rusting is a chemical process where iron reacts with oxygen and moisture to form iron oxide, which is an oxidation reaction.

Multiple choice

______ is the ability of metal to be drawn into thin wires.

  1. Malleability

  2. Ductility

  3. Metallurgy

  4. Electroplating
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ductility is the physical property of a metal that allows it to be stretched or drawn into a thin wire without breaking. Malleability, by contrast, refers to the ability to be hammered into thin sheets.

Multiple choice

When iron rusts, its weight

  1. increases

  2. decreases

  3. remains the same

  4. is unpredictable
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When iron rusts, it reacts with oxygen and moisture in the air to form iron oxide. Because oxygen atoms from the air are added to the iron, the total mass of the resulting substance increases.

Multiple choice

What is rust?

  1. It is an oxide of chromium.

  2. It is aluminium cholride.

  3. It is ferric chloride.

  4. It is a reddish brown hydrated oxide of iron.

  5. None of these
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Rust is a reddish brown hydrated oxide of iron. It is formed when iron is exposed to oxygen in the presence of moisture.