Chemistry Multiple Choice Questions on “Environmental Pollution”.
1. A substance, which causes pollution, is known as which of the following?
a) Pollutant
b) Carcinogen
c) Polluting element
d) Irritant
Answer: a
Clarification: A substance, causing pollution, is called as a pollutant. Pollutants can be solid, liquid, or gaseous substances present in greater concentrations than in natural abundance and are produced due to human activities or due to natural happenings. Carcinogens are substances, if exposed to, which can cause cancer. Irritants normally cause irritations to skin.
2. Identify the degradable pollutant from the following.
a) Chemicals
b) Metals
c) Discarded vegetables
d) Plastic
Answer: c
Clarification: Discarded vegetables are degradable pollutants. Since they are organic, they can be rapidly broken down by micro-organisms through natural processes. Chemicals, metals, and plastics are inorganic and they will slowly degrade, thereby, remaining in an unchanged form in the environment for many decades.
3. What is the full form of DDT?
a) Diphenyldichlorotrichloroethane
b) Dichlorodiphenyltrichloroethane
c) Dichlorodiphenyltriphenylethane
d) Dichlorodiphenyltrichloroethene
Answer: b
Clarification: The full form of DDT is dichlorodiphenyltrichloroethane. It is a colorless, tasteless, and almost odorless crystalline chemical compound. It was originally developed as an insecticide, but then, its use was stopped due to its harmful effect on environment as well as on the living organisms. If exposed to high concentrations, it can cause vomiting, seizures or tremors in human beings.
4. An average human being requires nearly 12-15 times more air than the food.
a) True
b) False
Answer: a
Clarification: An average human being requires nearly 12-15 times more air than the food. So, even small amounts of pollutants in the air become significant compared to similar levels present in the food. Therefore, the amount of people suffering various diseases due to contaminants in air is more than that suffering due to contaminants in food.
5. Which of the following is not a constituent of DDT?
a) Carbon
b) Fluorine
c) Chlorine
d) Hydrogen
Answer: b
Clarification: Fluorine is not a constituent of DDT. DDT is dichlorodiphenyltrichloroethane which has a chemical formula of C14H9Cl5. Therefore, DDT does not contain fluorine, which is evident from the chemical formula. It also contains impurities in small quantities, i.e., about 15% of its composition. The major component which comprises of 77% of the substance is its para isomer.