Ozone Layer Depletion

Q. The most abundant hydrocarbon pollutant is-

1. ethane
2. methane
3. propane
4. butane

Q. Which of the following is not a green house gas?

1. Carbon dioxide
2. water vapour
3. methane
4. oxygen gas

Q. Assertion (A): Use of Chlorofluorocarbons (CFC’s) is hazardous to environment. Reason (R): CFC’s are very reactive, flammable and toxic gases.

1. Both A and R are correct and R is the correct explanation of A.
2. A is not correct but R is correct.
3. Both A and R are correct but R is not the correct explanation of A.
4. A is correct but R are not correct.

Q. In Antarctica ozone depletion is due to formation of the following compound.

1. Acrolein

2. Peroxy acetyl nitrate

3. Sulphurdioxide and sulphur trioxide

4. Chlorine nitrate

Q. Which one is not correct? Greenhouse effect:

1. Would result in the warming up of the earth
2. Would result in lowering the level of oceans due to high evaporation
3. Is mainly due to high concentration of CO₂ in atmosphere
4. Is influenced by gases such as CH₄, O₃ and chlorofluorocarbons

Q. Ozone is formed in the upper atmosphere from oxygen by the action of:

1. UV rays
2. Cosmic rays
3. Nitrogen oxides
4. Free radicals

Q. Which of the following is incorrect?

1. Chlorofluorocarbons are responsible for ozone layer depletion
2. Greenhouse effect is responsible for global warming
3. Ozone layer does not permit infrared radiation from the sun to reach the earth
4. Acid rains is mostly because of oxides of nitrogen and sulphur

Q. Which of the following statement is true about the ozone layer?

1. It is harmful because ozone is dangerous to living organism
2. It is beneficial because oxidation reaction can proceed faster in the presence of ozone.
3. It is beneficial because ozone cuts off the UV radiation of the sun.
4. It is harmful because ozone cuts out the important radiations of the sun which are vital for photosynthesis.

Q. Acid rain has a pH of-

1. below 5.6
2. 5.6
3. 7.3
4. above 5.6

Q. $CFC{l}_3$ is responsible for the decomposition of ozone layer. Which of the following reacts with ozone to form oxygen?

1. Cl₂
2. Cl^-
3. F^-
4. Cl^*