2 Marks Question

How does nitrogen oxide destroy ozone layer? Write with chemical equation.
When nitrogen oxide are reached into the atmosphere it react with ozone and form oxygen with nitrogen dioxide. The nitrogen dioxide reacts with ozone layer and gradually destroys this layer.
Reaction:
NO + O₃ ⟶ NO₂ + O₂
2NO₂ + O₃ ⟶ N₂O₃ + 2O₂
How does chlorofluorocarbon destroy the ozone layer?
When chlorofluorocarbon (CFC) are reached into the atmosphere they deplete the ozone layer. UV rays dissociate CFC and form nascent chlorine. The nascent chlorine reacts with ozone layer and gradually destroys this layer.
Reaction:

$\ce{CFCl3 ->[uv rays] CFCL2 + Cl}$
$\ce{Cl + O3 ->[uv rays] ClO + O2}$
$\ce{2ClO ->[uv rays] 2Cl + O2}$
$\ce{Cl + CFCl2 ->[uv rays] CFCl3 (again)}$
Which layer of atmosphere is responsible for the change in weather? Why?
The troposphere is responsible for the change in weather because the climatic elements such as temperature, water and humid air associated with the troposphere account for the great variations in local climate and weather.
Which layer of atmosphere is called ionosphere? Why?
The thermosphere is called the ionosphere because of the greater effect of solar radiation the gaseous atoms are charged into ions.
Why do meteorologist give more importance to troposphere?
Meteorologists give more importance to the troposphere because the climatic elements such as temperature, water and humid air associated with the troposphere account for the great variations in local climate and weather. The forecasting of the weather is done by studying these factors.
Which layer of atmosphere helps in telecommunication, why?
The thermosphere helps in telecommunication because this layer helps in radio reception and the radio waves bounce off due to ions of this layer and get reflected back to the different parts of the earth.
The use of chlorofluorocarbon is not good, why? How is coal formed?
The use of chlorofluorocarbon is not good because when chlorofluorocarbons (CFC) are reached into the atmosphere they deplete the ozone layer. UV rays dissociate CFCs and form nascent chlorine. The nascent chlorine reacts with the ozone layer and gradually destroys this layer.
Reaction:
$\ce{CFCl3 ->[uv rays] CFCL2 + Cl}$
$\ce{Cl + O3 ->[uv rays] ClO + O2}$
$\ce{2ClO ->[uv rays] 2Cl + O2}$
$\ce{Cl + CFCl2 ->[uv rays] CFCl3 (again)}$

Millions and millions of years ago, the living beings (especially tall fern plants) were buried in the swampy land of earth. They were immediately covered by mud, stone etc. By extreme heat and pressure, carbon was extracted from them. It came from lignin, cellulose and hard parts. By slow chemical process, they were changed to coal.
Which layer of atmosphere contains ozone layer? Write any two importance of ozone layer.
Stratosphere contains ozone layer.
Any two importance of ozone layer are:
1. It absorbs about 99% of ultraviolet rays and prevent them from entering into earth surface.
2. It protects us from the diseases like blindness, skin cancer etc. caused due to harmful rays.
More info: Importance of ozone layer are: It helps to maintain suitable temperature of the earth, It preserves the ecosystem in the earth.
"Main cause of depletion of ozone layers is human being", How?
Chlorofluorocarbons (CFCs) are used as refrigerants by humans which is the major chemical to deplete the ozone layer. Similarly, different harmful gases from Industries like oxides of nitrogen also deplete the ozone layer which is developed by humans. Hence, the human being is the main cause of the depletion of the ozone layer.
Write any two effects of the increasing quantity of greenhouse gases in the atmosphere. Write with reasons.
Effects of the increasing quantity of greenhouse gases in the atmosphere are global warming, and ozone layer depletion because greenhouse gases like carbon dioxide, methane, and nitrous oxide absorb and emit some of the outgoing energy radiated from Earth's surface, causing that heat to be retained in the lower atmosphere.
The roof of an artificial greenhouse is made slanted, why?
The roof of an artificial greenhouse is made slanted so that maximum solar energy enters through it.
In present situation, the scientists have predicted that the surface temperature of earth is increasing. Write the reason.
In the present situation, the scientists have predicted that the surface the temperature of the earth is increasing because greenhouse gases are trapping more heat in the Earth's atmosphere, which is causing average temperatures to rise all over the world.
Atmosphere is called protective umbrella, why?
The atmosphere is called a protective umbrella because it does not allow the harmful UV radiations coming from the sun to reach the surface of the earth and thus protects life on the earth.
Write any two difference between coal and mineral oil.

Any two difference between coal and mineral oil are shown below in table:

Coal	Mineral
It is formed as a result of degradation of especially tall fern plants.	It is formed as a result of degradation of especially algae and animals.
It is used in electricity generation, steel production, cement manufacturing, etc.	It is used in transportation fuels, fuel oils for heating and electricity generation, road oil, etc.

The use of chlorofluorocarbon in refrigerator is not good, why?
The use of chlorofluorocarbon in the refrigerator is not good because if it releases in the atmosphere, it causes the ozone layer depletion due to which UV rays directly enter the earth and have adverse effects on living beings.