Ozone Layer Depletion

Q.

" damage to the ozone layer is a cause of concern "justify this statement. suggest any two steps to limit this damage

Q. The thin layer of ozone gas is present in the stratum of atmosphere called_______________.

1. Thermosphere
2. Stratosphere
3. Mesosphere
4. Troposphere

Q.

Why is our environment changing?

Q.

Which of the following gas causes a hole in the ozone layer?

1. Carbon dioxide

2. Chlorofluorocarbons

3. Sulphur dioxide

4. Oxygen

Q. Which of the following can be used instead of CFCs to prevent ozone layer depletion?

1. Fossil fuels
2. HFCs
3. HCIFCs
4. Both (b) and (c)

Q. Ozone at the higher levels of the atmosphere is a product of UV radiation acting on the _______ molecules.

1. $O_2$
2. $N_2$
3. $C{O}_2$
4. $H_2$

Q.

The following picture depicts a certain phenomenon.

(i) Name the phenomenon and explain it .

(ii) Enlist the sources that are responsible for the above mentioned phenomenon.

(iii) List out the effects of the above phenomenon on humans.

Q. Which of the following is not a preventive measure of ozone depletion?

1. Replacement of CFCs with alternative such as HFCs and HCFCs
2. Using alternative source of energy instead of fossil fuels
3. Using chlorinated insecticides and pesticides instead of biopesticides and bioinsecticides
4. Banning of harmful ozone depleting substances

Q.

What are chlorofluorocarbons? Why are they considered as air pollutants?

Q. The depletion of ozone layer is a cause of concern. Why?

Q. Assertion [A]: Deforestation is one of the main factors contributing to global warming.
Reason [R]: Besides $C{O}_2$, methane and CFCs are also greenhouse gases.

1. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
2. Assertion is true but Reason is false
3. Both Assertion and Reason are false
4. Both Assertion and reason are true and Reason is the correct explanation of Assertion

Q.

Why are CFCs banned?

Q.

CFCs convert oxygen to ozone.

1. True

2. False

Q.

Ozone formed at the Earth's surface, is a deadly poison.

1. True

2. False

Q.

What is the major cause of ozone layer depletion?

Q.

The major cause for depletion of ozone layer in stratosphere is due to the

1. increase in the level of greenhouse gases

2. decreased use of CFCs

3. increase in sulphur dioxide and carbon monoxide

4. increased usage of CFCs

Q. Which organisation played an important role in forging an agreement to freeze CFC production?

1. UNESCO
2. UNICEF
3. UNEP
4. OPCW

Q. Ozone-layer is getting depleted because of

1. Excessive use of automobiles
   
2. Excessive formation of industrial units
   
3. Excessive use of man-made compounds containing both fluorine and chlorine
   
4. Excessive deforestation.

Q. Amount of atmospheric ozone is measured by

1. Greenhouse effect
2. Punnett square
3. Biogeochemical cycle
4. Dobson spectrometer

Q. Regarding the assertion and reason, choose the correct option.
Assertion [A]: Deforestation is one main factor contributing to global warming.
Reason [R]: Besides, $C{O}_2$, methane and CFCs are also greenhouse gases.

1. Both Assertion and reason are true and Reason is the correct explanation of Assertion
2. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
3. Assertion is true but Reason is false
4. Both Assertion and Reason are false

Q.

The Ozone hole is maximum over

1. Europe

2. Antarctica

3. India

4. Africa

Q. Regarding the assertion and reason, choose the correct option:
Assertion [A]: Methane component of greenhouse gases contributes to global warming by about 20 percent.
Reason [R]: Introduction of multipoint fuel injection engines in automobiles has decreased methane content in exhausts.

1. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
2. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
3. Assertion is true but Reason is false
4. Both Assertion and Reason are false

Q.

The thickness of stratospheric ozone layer is measured in/on.

1. Sieverts

2. Dobson units

3. Melson units

4. Beaufort scale

Q. Regarding the assertion and reason, choose the correct option.
Assertion [A]: Deforestation is one main factor contributing to global warming.
Reason [R]: Besides CO₂, methane and CFCs are also greenhouse gases.

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

Q.

We know that the percentage of oxygen in air is decreasing and that of carbon dioxide is increasing. What would happen if this does not stop? What can we do to stop this ?

Q. Regarding the assertion and reason, choose the correct option.
Assertion [A]: Deforestation is one main factor contributing to global warming.
Reason [R]: Besides, $C{O}_2$, methane and CFCs are also greenhouse gases.

1. Both Assertion and reason are true and Reason is the correct explanation of Assertion
2. Both Assertion and Reason are false
3. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
4. Assertion is true but Reason is false

Q. In the upper atmosphere ___ gets converted to ozone.

Q.

(a) Name the three gases which destroy ozone layer.

(b) What consequences will follow with the destruction of ozone layer.

(c) Suggest two methods to control depletion of ozone layer.

Q. Which of the following green house gas depletes ozone layer?

1. Chlorofluorocarbon
2. Methane
3. Carbon Dioxide
4. Nitrogen Dioxide

Q. Regarding the assertion and reason, choose the correct option.
Assertion [A]: UV radiation causes photo-dissociation of ozone into O₂ and O, thus causing damage to the ozone layer.
Reason [R]: The ozone hole has been the major cause of global warming and climate change.

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