Tag: air around us

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Questions Related to air around us

Multiple choice chemistry air around us importance of oxygen is air present everywhere around us? air as a natural resource

Ozone hole means :

  1. thinning of the ozone layer

  2. a large sized hole in ozone layer

  3. small hole scattered in the ozone layer

  4. thickening of ozone in ozone layer
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

"Ozone hole" means thinning of the ozone layer.


The ozone hole is not technically a “hole” where no ozone is present but is actually a region of exceptionally depleted ozone layer.

Hence the option A is correct.

Multiple choice chemistry air around us importance of oxygen is air present everywhere around us? air as a natural resource

Choose the correct answer form the alternatives given.
Scuba divers are at high risk due to high concentration of dissolved gases while breathing air at high pressure under water. The tanks used by Scuba divers are filled with :-

  1. Air diluted with helium

  2. 02

  3. N

  4. A mixture of nitrogen and helium
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Scuba divers use a mixture of gases to avoid nitrogen narcosis and oxygen toxicity at high pressures. Helium is often used to dilute the mixture because it is inert and less soluble in blood than nitrogen.

Multiple choice chemistry air around us importance of oxygen is air present everywhere around us? air as a natural resource

The nitrogen molecules present in the air can be converted into nitrates and nitrites by :

  1. nitrogen fixation

  2. carbon fixation

  3. industries in the form of by ctprodu

  4. cereal plants
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The nitrogen molecules present in the air can be converted into nitrates and nitrites by nitrogen fixation.


Hence the option A is correct.

Multiple choice chemistry air around us importance of oxygen is air present everywhere around us? air as a natural resource

The part of atmosphere which contains constant gases with known composition called :

  1. Homosphere

  2. Thermosphere

  3. Heterosphere

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The part of the atmosphere which contains constant gases with a known composition called homo-sphere.

The homosphere is the lower of the two and the location in which turbulent mixing dominates the molecular diffusion of gases. In this region, which occurs below 100 km (about 60 miles) or so, the composition of the atmosphere tends to be independent of height.

Multiple choice water and air and their importance natural resources- air, water and land air around us air chemistry introduction to natural resources land

Which is a green house gas?
A) Methane 

B) Chlorofluorocarbons 
C) $CO _{2}$

  1. $A$ and $B$
  2. $B$ and $C$
  3. $C$ and $D$
  4. $A, B$ and $C$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Greenhouse effect
* The progressive heating up of surface of the earth is earth is called green house effect or global warming.
 $CO _2$ and $H _2O$ block a part of the heat (IR) emitted by the earth & reflect back. Due to this earth surface gets heated up.
 50% in $CO _2$ content of air can increase the surface temperature of the earth by $3^oC$.
* In addition to $CO _2$ , the other green - house gases are CFCs (17%), $O _3$ (18%), NO (4%), water vapour (2%).

Multiple choice water and air and their importance natural resources- air, water and land air around us air chemistry introduction to natural resources land

Which of the following is not a sink for CO?

  1. Haemoglobin

  2. Microorganims present in the soil

  3. Oceans

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation


* Incomplete combustion of fossil fuels liberate CO into air. 80% of CO is released from automobiles.


* Permissible level of CO in air is 9 ppm. It reduces $O _2$ supply in human by forming a stable carboxyhaemoglobin.

$2C+O _2\rightarrow 2CO$
$2CH _4+3O _2\rightarrow 2CO+4H _2O$

* CO interacts with oxyhaemoglobin ($O _2Hb$) and forms carboxyhaemoglobin (CO-Hb) as :

$O _2Hb+CO\rightarrow COHb+O _2$

* CO has high affinity for haemoglobin than that of oxygen.

Therefore, option A is correct.

Multiple choice water and air and their importance natural resources- air, water and land air around us air chemistry introduction to natural resources land

The most problematic gases emitted in a volcanic eruption includes :

  1. sulphur dioxide

  2. carbon dioxide

  3. hydrogen fluoride

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Volcanic eruptions release a variety of gases, including sulfur dioxide, carbon dioxide, and hydrogen fluoride, all of which pose environmental and health risks.