Chemistry

Environmental Chemistry

Question:

What would have happened if the greenhouse gases were totally missing in the earth’s atmosphere? Discuss.

Answer:

The solar energy radiated back from the earth surface is absorbed by the green house gases. (CO2, CH4, O3, CFCs) are present near the earth’s surface.
They heat up the atmosphere near the earth’s surface and keep it warm. As a result of these, there is growth of vegetation which supports the life. In the absence of this effect, there will be no life of both plant and animal on the surface of the earth.

previuos
next

Environmental Chemistry

Q 1.

Ozone is a toxic gas and is a strong oxidizing agent, even then its presence in the stratosphere is very important. Explain what would happen if ozone from this region is completely removed.

Q 2.

Acid rain is known to contain some acids. Name these acids. From where do they come in rain?

Q 3.

Assertion (A): Excessive use of chlorinated synthetic pesticides causes soil and water pollution.
Reason (R): Such pesticides are non-biodegradable.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) Both A and R are not correct.
(d) A is not correct but R is correct.

Q 4.

How can domestic waste be used as manure?

Q 5.

What is photochemical smog? What are its effects? How can it be controlled?

Q 6.

Oxidation of sulphur trioxide in the absence of a catalyst is a slow process but this oxidation occurs easily in the atmosphere. Explain how does this happen. Give chemical reactions for the conversion of S02 into S03.

Q 7.

List out the gases which are considered as major source of air pollution.

Q 8.

Why is acid rain considered as threat to Taj Mahal ?

Q 9.

What are the sources of dissolved oxygen in water?

Q 10.

Which of the following conditions shows the polluted environment?
(a) pH of rain water is 5.6.
(b) Amount of carbon dioxide in the atmosphere is 0.03%.
(c) Biochemical oxygen demand is 10 ppm.
(d) Eutrophication

Q 11.

What would have happened if the greenhouse gases were totally missing in the earth’s atmosphere? Discuss.

Q 12.

What is PAN stands for?

Q 13.

What do you mean by viable and non-viable particulates?

Q 14.

What is siltation?

Q 15.

Which zone is known as ozonosphere?

Q 16.

What is BOD?

Q 17.

Assertion (A): If BOD level of water in a reservoir is less than 5 ppm it is highly polluted.
Reason (R): High biological oxygen demand means low activity of bacteria in water.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) Both A and R are not correct.
(d) A is not correct but R is correct.

Q 18.

What is smog? How is classical smog different from photochemical smog?

Q 19.

Why does water covered with excessive algal growth become polluted?

Q 20.

Assertion (A): The pH of acid rain is less than 5.6.
Reason (R): Carbon dioxide present in the atmosphere dissolves in rain water and forms carbonic acid.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) Both A and R are not correct.
(d) A is not correct but R is correct.

Q 21.

How carbon monoxide acts as a poison for human beings?

Q 22.

From where does ozone come in the photochemical smog?

Q 23.

Define environmental chemistry?

Q 24.

What are pesticides and herbicides? Explain giving examples.

Q 25.

What is the name of the compound formed when CO combines with blood?

Q 26.

Which of the following statements is correct?
(a) Ozone hole is a hole formed in stratosphere from which ozone oozes out.
(b) Ozone hole is a hole formed in the troposphere from which ozone oozes out.                                                                                                                                                 .
(c) Ozone hole is thinning of ozone layer of stratosphere at some places.
(d) Ozone hole means vanishing of ozone layer around the earth completely.

Q 27.

Carbon monoxide gas is more dangerous than carbon dioxide gas. Why?

Q 28.

What are the major causes of water pollution? Explain.

Q 29.

What is ‘Acid Rain’? How is it harmful to the environment?

Q 30.

What is meant by PCBs?

Q 31.

What do you mean by green chemistry? How will it help in decreasing environmental pollution ?

Q 32.

Which gas was mainly responsible for Bhopal gas tragedy?  

Q 33.

What are biodegradable and non-biodegradable pollutants? ,

Q 34.

Which main gases is responsible for damage in ozone layer?

Q 35.

What is the nature of classical smog?

Q 36.

Phosphate containing fertilizers cause water pollution. Addition of such compounds in water bodies causes
(a) enhanced growth of algae
(b) decrease in amount of dissolved oxygen in water
(c) deposition of calcium phosphate
(d) increase in fish population

Q 37.

For your agricultural field or garden you have developed a compost producing pit. Discuss the process in the light of bad odour, flies and recycling of wastes for a good produce.

Q 38.

How are NO and NO2 formed in the atmosphere?

Q 39.

What is chlorosis?

Q 40.

What is the compound formed when CO combines with blood?

Q 41.

The acids present in acid rain are________ .
(a) Peroxyacetylnitrate                                                
(b) H2C03
(c) HN03                                                                                                    
(d) H2S04

Q 42.

What could be the harmful effects of improper management of industrial and domestic solid waste in a city?

Q 43.

What is the importance of measuring BOD of a water body?

Q 44.

A factory was started near a village. Suddenly villagers started feeling the presence of irritating vapours in the village and cases of headache, chest pain, cough, dryness of throat and breathing problems increased. Villagers blamed the emissions from the chimney of the factory for such problems. Explain what could have happened. Give chemical reactions for the support of your explanation.

Q 45.

Sometime ago formation of polar stratospheric clouds was reported over Antarctica. Why were these formed? What happens when such clouds break up by warmth of sunlight?

Q 46.

A person was using water supplied by Municipality. Due to shortage of water, he started using underground water. He felt laxative effect. What could be the cause?

Q 47.

Assertion (A): Photochemical smog is oxidizing in nature.
Reason (R): Photochemical smog contains N02 and 03, which are formed during the sequence of reactions.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) Both A and R are not correct.
(d) A is not correct but R is correct.

Q 48.

Assertion (A): Carbon dioxide is one of the important greenhouse gases. Reason (R): It is largely produced by respiratory function of animals and plants.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) Both A and R are not correct.
(d) A is not correct but R is correct.

Q 49.

Assertion (A): Ozone is destroyed by solar radiation in upper stratosphere.
Reason (R): Thinning of the ozone layer allows excessive UV radiations to reach the surface of earth.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) Both A and R are not correct.
(d) A is not correct but R is correct.

Q 50.

What are the harmful effects of photochemical smog and how can they be controlled?