Tag: planet earth

Questions Related to planet earth

Rain, snow or fog, which is acidic in nature, is known as:

chemistry planet earth acid deposition air and air pollution natural resources- air, water and land

  1. acid rain

  2. acid snow

  3. acid fog

  4. all of the above

Show answer
Correct Option: A
Explanation:

Acid rain includes any form of precipitation with acidic components from the atmosphere.

This can include rain, snow, fog, hail or even dust that is acidic.
This happens when oxides of sulphur and nitrogen that are emitted by the industries react with water and oxygen in the atmosphere to form sulphuric acid and nitric acid respectively.
These acids are responsible for the acidic nature of the rains. Their pH is usually between 5.5 to 5.
Thus, the correct answer is option (A).

Which of the following gases related with acid rain?

chemistry planet earth acid deposition air and air pollution natural resources- air, water and land

  1. ${ NO } _{ 2 }$ and ${ CO } _{ 2 }$

  2. ${ CH } _{ 4 }$ and ${ SO } _{ 2 }$

  3. ${ CO } _{ 2 }$ and ${ SO } _{ 2 }$

  4. ${ SO } _{ 2 }$ and ${ NO } _{ 2 }$

Show answer
Correct Option: D
Explanation:

${ SO } _{ 2 }$ and ${ NO } _{ 2 }$:burning of fossil fuels releases oxides of sulphur and nitrogen, ${ SO } _{ 2 }$ and ${ NO } _{ 2 }$ reacts with water and oxygen and other chemicals to form sulphuric acid and nitric acid.

 Acid rain happens because:

chemistry planet earth acid deposition air and air pollution natural resources- air, water and land

  1. sun leads to heating of upper layer of atmosphere

  2. the burning of fossil fuels release oxides of carbon, nitrogen, and sulphur in the atmosphere

  3. electrical charges are produced due to friction amongst clouds

  4. earth atmosphere contains acids

Show answer
Correct Option: B
Explanation:

 Acid rain is caused by emissions of acidic gases like sulphur dioxide, nitrogen and carbon oxides, which react with the water  molecules in the atmosphere to produce acids. 

Assertion(A) : Rainwater normally has a $pH$ $= $ 5.6


Reason (R) : This is due to the presence of $H _{2}SO _{4}$ and $HNO _{3}$ produced from oxides of sulphur and nitrogen.

chemistry planet earth acid deposition air and air pollution natural resources- air, water and land

  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 correct explanation of A.

  3. A is true and R is false.

  4. A is false and R is true

Show answer
Correct Option: C
Explanation:
Normal rain has a pH of about 5.6. This is because it reacts with carbon dioxide in the atmosphere and forms mildly acidic carbonic acid before it becomes rain.

Acid rains occur due to oxides of nitrogen and sulphur.

Nitric acid & sulphuric acid in the atmosphere dissolve in rainwater and come down to earth as acid rain. 

Acid rains have a pH 4.

Therefore, option C is correct

Assertion (A): The oxides of nitrogen and sulphur combine with rainwater and come down as acid rain.
Reason (R): Acid rains cause depletion of ozone layer.

chemistry planet earth acid deposition air and air pollution natural resources- air, water and land

  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 correct explanation of A

  3. A is true and R is false

  4. A is false and R is true

Show answer
Correct Option: C
Explanation:

Below are few properties of acid rain:
1) Acid rains are obtained due to oxides of nitrogen & sulphur.
2) Nitric acid and sulphuric acid in the atmosphere dissolve in rain water and come down to earth as acid rain. 
3) It may have a pH less than 5.6
4) There is no relation of acid rain with ozone layer.

Which of the following gases will not cause acid rain?

chemistry planet earth acid deposition air and air pollution natural resources- air, water and land

  1. $SO _2$

  2. $NO _2$

  3. $CO _2$

  4. $O _3$

Show answer
Correct Option: D
Explanation:
Sulphur present in any fuel combines with oxygen and forms $SO _2$ in the combustion chamber. $SO _2$ when emitted into the atmosphere, it oxidizes to form $SO _3$. It is soluble in water in the clouds and forms $H _2SO _4$ (Sulphuric acid).

$S+O _2 \rightarrow SO _2 +\dfrac {1}{2} O _2 \longrightarrow SO _3+H _2O\rightarrow H _2SO _4$

Most of the $NO _x$ emitted in the form in the forms of $NO$.
This $NO$ oxidised in the atmosphere to form $NO _2$.
$NO _2$ is soluble in water and form $HNO _3$ (Nitric Acid).

$NO+\dfrac {1}{2}O _2\rightarrow NO _2+H _2O\rightarrow HNO _3$ 
                       
Carbon divide reacts with water to form carbonic acid. Carbonic acid then dissociates to give the hydrogen ion $(H^+)$ and the hydrogen carbonate ion $(HCO _3^-)$. The ability of $H _2CO _3$ to deliver $H^+$ classifies this molecule as acid.

$CO _2 +H _2O\longrightarrow H _2CO _3$

$H _2CO _3 \longrightarrow H^++HCO _3^-$

For $O _3$,
$O _3+$Ultraviolet $\rightarrow O+O _2$

$O+O _3\rightarrow 2O _2$

Net Reaction: $2O _3+ UV\rightarrow 3O _2$

It does from any acidic component therefore $O _3$ will not cause acid rain.

Acid rains are produced by:

chemistry planet earth acid deposition air and air pollution natural resources- air, water and land

  1. excess ${NO} _{2}$ and ${SO} _{2}$ from burning fossil fuels

  2. excess production of ${NH} _{3}$ by industry and coal gas

  3. excess release of carbon monoxide by incomplete combustion

  4. excess formation of ${CO} _{2}$ by combustion and animal respiration

Show answer
Correct Option: A

Temperature of troposphere decreases with altitude. This is because of_____.

chemistry planet earth acid deposition air and air pollution natural resources- air, water and land

  1. high pressure of air

  2. gases present in air

  3. low density of air

  4. all of these

Show answer
Correct Option: A
Explanation:
Generally, temperatures decrease with increasing height because the atmosphere distributes itself according to gravity.

In the troposphere, the temperature generally decreases with altitude. The reason is the troposphere's gases absorb very little of the incoming solar radiation. Instead, the ground absorbs this radiation and then heats the tropospheric air by conduction and convection.

Which of the folowing oxides of nitrogen is not a common air pollutant ?

chemistry planet earth acid deposition air and air pollution natural resources- air, water and land

  1. $ NO _2$

  2. $ N _2O $

  3. $ NO $

  4. $ N _2O _5 $

Show answer
Correct Option: D
The production of dihydrogen gas via water gas shift reaction,
 
$CO(g) + H _2O (g) \xrightarrow {\Delta/Catalyst} CO _2(g) + H _2(g).$

The $CO _2$ gas is removed by scrubbing with solution of 
chemistry planet earth acid deposition air and air pollution natural resources- air, water and land

  1. sodium arsenite

  2. calcium oxide

  3. sodium phosphate

  4. aluminium oxide

Show answer
Correct Option: A
Explanation:

The water-gas shift reaction (WGSR) describes  the reaction of carbon monoxide and water vapour to form carbon dioxide and hydrogen (the mixture of carbon monoxide and hydrogen is known as water gas)

$CO(g) + H _2O (g) \xrightarrow {\Delta/FeCrO _4} CO _2(g) + H _2(g).$

The carbondioxide obtained in the above reaction is removed by scrubbing with solution of sodium arsenite.