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Select the correct statements. Chloro...

Select the correct statements.
Chlorofluorocarbons (CFCs) react with the Ozone gas of ozone layer and destroy it gradually.
(ii) Carbon monoxide combines with haemoglobin of blood and prevents transport of oxygen by it.
(iii) Electrostatic precipitators are used to remove particles of solids such as carbon from factories.
(iv) Use of leaded petrol reduces the release of harmful pollutants into the air.

A

(i), (ii) and (iii) only

B

(i) and (ii) only

C

(ii) and (iv) only

D

(iii) and (iv) only

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to evaluate each of the four statements provided and determine which ones are correct. ### Step-by-Step Solution: 1. **Evaluate Statement (i)**: - **Statement**: Chlorofluorocarbons (CFCs) react with the ozone gas of the ozone layer and destroy it gradually. - **Analysis**: This statement is correct. CFCs are known to deplete the ozone layer, which protects us from harmful UV radiation. 2. **Evaluate Statement (ii)**: - **Statement**: Carbon monoxide combines with hemoglobin of blood and prevents transport of oxygen by it. - **Analysis**: This statement is also correct. Carbon monoxide binds with hemoglobin more effectively than oxygen, which prevents oxygen transport in the body. 3. **Evaluate Statement (iii)**: - **Statement**: Electrostatic precipitators are used to remove particles of solids such as carbon from factories. - **Analysis**: This statement is correct. Electrostatic precipitators are devices used in industries to reduce air pollution by removing solid particles from the air. 4. **Evaluate Statement (iv)**: - **Statement**: Use of leaded petrol reduces the release of harmful pollutants into the air. - **Analysis**: This statement is incorrect. Leaded petrol actually contributes to air pollution, and it is better to use unleaded petrol to minimize harmful emissions. ### Conclusion: - The correct statements are (i), (ii), and (iii). - Therefore, the answer is: **Statements (i), (ii), and (iii) are correct.**
To solve the question, we need to evaluate each of the four statements provided and determine which ones are correct. ### Step-by-Step Solution: 1. **Evaluate Statement (i)**: - **Statement**: Chlorofluorocarbons (CFCs) react with the ozone gas of the ozone layer and destroy it gradually. - **Analysis**: This statement is correct. CFCs are known to deplete the ozone layer, which protects us from harmful UV radiation. ...
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