Practice MCQ Questions and answers on Chemistry-GK

11

Which type of fire extinguisher is used for petroleum fire ?

A) Foam type B) Soda acid type
C) Powder type
D) None of these

Discuss

Answer & Solution

Answer: Option C

Solution:

Powder type extinguisher is used for petroleum fire.

12

Man dies in the atmosphere of CO, because it

A) Dries up the blood B) Combines with O₂ present in the body C) Reduces the organic matter of tissues D) Combines with the haemoglobin of blood, thereby making the later incapable of absorbing O₂

Discuss

Answer & Solution

Answer: Option D

Solution:

The preferential binding of carbon monoxide to iron severely limits the oxygen to bind to hemoglobin. As a result, less oxygen is carried through our system and we die.

13

It is dangerous to leave the car engine running in a closed garage, because it may cause serious pollution due to poisoning by emission of

A) CO₂ B) CO C) Unburnt petrol D) SO₂

Discuss

Answer & Solution

Answer: Option B

Solution:

The extremely high concentrations of carbon monoxide produced by an engine can raise CO concentrations in a closed building so quickly that a person may collapse before they even realize there is a problem.
Carbon monoxide reduces the amount of oxygen to the brain, causing CO intoxication, and lack of reasoning. Hence option D is correct answer.

14

Which gas is used as fire extinguisher ?

A) Carbon dioxide B) Carbon monoxide C) Carbon suboxide D) Sulphur dioxide

Discuss

Answer & Solution

Answer: Option A

Solution:

Carbon dioxide is used as fire extinguisher.

15

The process which does not evolve CO₂ in air is

A) Burning B) Breathing C) Organic delay D) Photosynthesis

Discuss

Answer & Solution

Answer: Option D

Solution:

The process which does not evolve CO₂ in air is photosynthesis.

16

The metal used to galvanise iron to protect it from rusting is

A) Zinc
B) Chromium C) Lead D) Antimony

Discuss

Answer & Solution

Answer: Option A

Solution:

Galvanisation or galvanization (or galvanizing as it is most commonly called) is the process of applying a protective zinc coating to iron or steel, to prevent rusting.

17

Iron is prevented from rusting by coating with zinc. This process is called as

A) Galvanisation B) Corrosion C) Sublimation D) Reduction

Discuss

Answer & Solution

Answer: Option A

Solution:

Iron is prevented from rusting by coating with zinc. This process is called as galvanisation.

18

An electric iron has a heating element made of :

A) Copper
B) Tungsten
C) Nichrome
D) Zinc

Discuss

Answer & Solution

Answer: Option C

Solution:

Nichrome is Used in an Electric Iron as a heating Element . It is an alloy of Nickel and Chromium with 80 % Nickel and 20 % Chromium. It has a high melting Point of 1400 degree Celsius.

19

The metal chiefly used for galvanising iron is :

A) Zinc B) Mercury C) Cadmium D) Tin

Discuss

Answer & Solution

Answer: Option A

Solution:

Galvanisation or galvanization (or galvanizing as it is most commonly called) is the process of applying a protective zinc coating to iron or steel, to prevent rusting. The most common method is hot dip galvanizing, in which steel sections are submerged in a bath of molten zinc.

20

The anode in a dry cell consists of

A) Copper B) Zinc C) Cadmium D) Graphite

Discuss

Answer & Solution

Answer: Option B

Solution:

A standard dry cell comprises a zinc anode, usually in the form of a cylindrical pot, with a carbon cathode in the form of a central rod. The electrolyte is ammonium chloride in the form of a paste next to the zinc anode.