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Exercise solution

 Question 3: Explain temperature variations in stratosphere and troposphere.

Answer.

In troposphere, temperature decreases as altitude increases. Air is warmer near earth and cooler at the top. In this layer, the maximum temperature is 17 oC  and minimum temperature is -55 Oc. On average, for every 1 km increase in altitude, the air gets cool down to 6.5 Oc. 

On the other hand, in stratosphere, the temperature increases with increase in altitude. Upper  stratosphere is warmer than lower stratosphere due to formation of ozone and release of heat energy. In this layer, the temperature varies from -55 Oc to -5 OC. 




Question 4: List components of stratosphere and troposphere.

Answer. 

Stratosphere

Troposphere

Question 5: Describe sources of air pollutants

Answer.

Sources of Air Pollutants

Question 6: Describe acid rain and its effects.

Answer: 

Question 7: Describe ozone depletion and its effects.

Answer.

Question 8: Describe global warming.

Answer.

Question 9: Differentiate between stratosphere and troposphere.

Answer.

Stratosphere

Troposphere

Question 10: Describe the ozone formation.

Answer.

Ozone formation

Question 11: Why is global warming often referred to as the greenhouse effect?

Answer. Global warming is the process of overall gradual increase in temperature of earth. As greenhouse gases are increasing day by day in our atmosphere due to combustion of fossil fuels, the  temperature of atmosphere is increasing causing global warming.  Therefore, global warming is also referred as greenhouse effect. 

Question 12: There is scientific evidence that CFCs contribute to the depletion of ozone. Why?

Answer. 

Ozone depletion

Question 13: Sulphur dioxide is a common pollutant from burning coal. State two effects caused by this pollutant.

Answer

1. Sulphur dioxide (SO2)  reduces lung function, increases the respiratory disease and causes irritation of eyes, nose and throat.

Sulphur dioxide reacts with oxygen to form sulphur trioxide (SO3) that dissolves in rain water and causes acidic rain.




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  1. UnknownDecember 26, 2020 at 6:47 PM

    Particularly...such graph is much needed to explain variations in temperature..a nice effort

    ReplyDelete

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