Choose the correct answer from the options given below: 

1. Both Statement I and Statement II are false.
2. Statement I is true but Statement II is false.
3. Both Statement I and Statement II are true.
4. Statement I is false but Statement II is true.

Water does not produce CO on reacting with-

1. CO₂

2. C

3. CH₄

4. C₃H₈

Given below are two statements :

Statement I: The pH of rainwater is normally ~5.6.

Statement II: If the pH of rainwater drops below 5.6, it is called acid rain.

1. Statement I is true but Statement II is false.

2. Both Statement I and Statement II are false.

3. Statement I is false but Statement II is true.

4. Both Statement I and Statement II are true.

The presence of ozone in the troposphere-

1. Protects us from UV radiation.

2. Protects us from X-ray radiation.

3. Protects us from the greenhouse effect.

4. Generates photochemical smog.

Incorrect statement among the following regarding ozone is-

1. In the stratosphere, it forms a protective shield against UV radiation.

2. It is a toxic gas and its reaction with NO gives NO₂.

3. In the stratosphere, CFCs release chlorine-free radicals which react with O₃ to give chlorine dioxide radicals.

4. In the atmosphere, it is depleted by CFCs.

The gas released during anaerobic degradation of vegetation may lead to:

1. Ozone hole

2. Acid rain

3. Corrosion of metals

4. Global warming and cancer

Thermal power plants can lead to-
1. Eutrophication
2. Acid rain
3. Blue baby syndrome
4. Ozone layer depletion

The incorrect statement(s)  regarding acid rain is/are-
1. It can corrode water pipes
2. It can damage structures made up of stone
3. It cannot cause respiratory ailments in animals
4. It is  harmful for trees