Tag: chemistry

Questions Related to chemistry

Suspended particulate matter like __________ emitted from industries causes yellowing of marble.

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

  1. dust particles

  2. acidic gases

  3. soot particles

  4. all of the above

Show answer
Correct Option: C
Explanation:

Industries like Mathura Oil refinery near Agra emits certain suspended particulate matter like soot particles. This results in yellowing of marble of the monument.

Which of the following is correct about acid rain?

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

  1. Rain which is acidic in nature

  2. Rain which is basic in nature

  3. Rain which is neutral in nature

  4. All of the above

Show answer
Correct Option: A
Explanation:

When oxides of sulphur and nitrogen which are emitted by the industries, react with the moisture present in the atmosphere, they form acids.

Thus, these acids reduce the pH of the rain falling on the Earth and hence acid rain is acidic in nature.
It's pH acid  rain is 5.5
Hence, the correct answer is option (A).

Which of the following statements is true about acid rain? 

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

  1. Acid rain will erode marble statues

  2. Acid rain can change the pH of lakes and streams

  3. Acid rain can be formed from carbon dioxide

  4. Acid rain creates holes in the ozone layer

  5. All of the above

Show answer
Correct Option: E
Explanation:

Acid rain is caused due to oxides of nitrogen and sulphur reacting with water, oxygen, carbon dioxide, and other chemicals present high in the atmosphere resulting into acidic pollutants.

As a result of this, $pH$ of rainwater lowers down to $5$ resulting in $pH$ change of lakes and streams.
It also reacts with calcium carbonate present in the marbles causing weathering. 
The oxides of sulphur may also react with $O _3$ present in ozone, thus depleting the ozone layer. Hence all the given statements are correct

Ozone is an air pollutant that is a major component of:

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

  1. smog

  2. smoke

  3. dust

  4. dirt particles

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Correct Option: A
Explanation:

At ground level, ozone is an air pollutant that is a major component of smog which is dangerous for both humans and plants. Long-term ozone exposure has also been shown to reduce life expectancy. 

Acid rain is caused by emissions of:

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

  1. sulphur dioxide

  2. nitrogen dioxide

  3. both $A$ and $B$

  4. hydrogen

Show answer
Correct Option: C
Explanation:

Acid rain is a rain or any other form of precipitation that is unusually acidic, meaning that it possesses elevated levels of hydrogen ions (low pH). It can have harmful effects on plants, aquatic animals and infrastructure. Acid rain is caused by emissions of sulfur dioxide and nitrogen oxide, which react with the water molecules in the atmosphere to produce acids. 

Over a number of years the average pH of a stream changes from a pH of 6.9 to a pH of 5.9 due to acid rain. Which statement is true about the pH of the stream?

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

  1. The pH of the stream now is one times more acidic than it was years ago

  2. The stream now has 10 times more hydroxide ions than it did years ago

  3. The pH of the stream is now 10 times more acidic than it was years ago

  4. The stream is more basic now than it was years ago

  5. The concentration of hydronium ion in the stream has decreased over the years

Show answer
Correct Option: C
Explanation:

Over a number of years the average pH of a stream changes from a pH of 6.9 to a pH of 5.9 due to acid rain. The pH of the stream is now 10 times more acidic than it was years ago.
Years ago, the pH was 6.9. The present day pH is 5.9. The change in pH is
$\displaystyle  = \Delta pH= 5.9-6.9 = -1$
The corresponding change in hydrogen ion concentration is:
$\displaystyle 10^{-\Delta pH}= 10^{-(-1)} = 10$

Which of the following is a major natural cause for acid rain?

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

  1. Earthquakes

  2. Cyclones

  3. Volcanoes

  4. Thunderstorm

Show answer
Correct Option: C
Explanation:

The major natural causal agent for acid rain is volcanic emissions. Volcanoes emit acid producing gases to create higher than normal amounts of acid rain or any other form of precipitation such as fog and snow to an extent of affecting vegetation cover and health of residents within the surrounding. 

In the gases below, which would react with rain water to produce acid rain?
i. CFCs
ii. Methane
iii. Carbon dioxide

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

  1. i only

  2. ii only

  3. iii only

  4. i and iii only

  5. i, ii and iii

Show answer
Correct Option: C
Explanation:

Carbon dioxide would react with rainwater to produce acid rain.


The reaction of carbon dioxide with water gives carbonic acid.

$\displaystyle CO _2 + H _2O \rightarrow H _2CO _3 $

  • Hence the correct option is C.

Which is among the greatest contributors to gaseous pollutions that are responsible for acidic rain?

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

  1. Electrical power generation using coal

  2. Earthquakes

  3. Air pollution

  4. All of the above

Show answer
Correct Option: A
Explanation:

The principal cause of acid rain is sulfur and nitrogen compounds from human sources, such as electricity generation, factories, and motor vehicles. Electrical power generation using coal is among the greatest contributors to gaseous pollutions that are responsible for acidic rain. The gases can be carried hundreds of kilometers in the atmosphere before they are converted to acids and deposited.

Photochemical smog is the chemical reaction of sunlight, nitrogen oxides and volatile ________ compounds in the atmosphere, which leaves airborne particles and ground-level ozone.

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

  1. hydrocarbons

  2. inorganic compounds

  3. sulphates

  4. carbonates

Show answer
Correct Option: A
Explanation:

Photochemical smog is the chemical reaction of sunlight, nitrogen oxides and volatile organic compounds in the atmosphere, which leaves airborne particles and ground-level ozone.
Hence option A is the correct answer.