Tag: water and air and their importance

Quizzes (14) Questions (139)

Questions Related to water and air and their importance

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

To increase the percentage of oxygen in the atmosphere :

  1. plant more trees

  2. kill all living beings

  3. cut down trees

  4. protect animal life
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Planting more trees directly increases the oxygen amount by the process of photosynthesis which in turn increases the percentage of oxygen in the atmosphere.

Hence the option A is correct.
Multiple choice chemistry water and air and their importance importance of oxygen is air present everywhere around us? air as a natural resource

Plant consume ________ to make their own food.

  1. Oxygen

  2. Carbon dioxide

  3. Both A and B

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

Plant consume carbon dioxide, water and other nutrients to make their own food.


The leaves contain a pigment called chlorophyll, which colours the leaves green. 


Chlorophyll can make food the plant can use from carbon dioxide, water, nutrients, and energy from sunlight. This process is called photosynthesis.


Hence the option B is correct.

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

Which of the following is incorrect regarding oxygen?

  1. Solid oxygen is blue.

  2. Oxygen gas is odorless.

  3. Oxygen is non-toxic.

  4. Liquid and solid oxygen are paramagnetic.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Solid oxygen is a clear substance with a light sky-blue colour. Oxygen gas is a colourless gas without taste or odour. Oxygen toxicity is a condition that results from the harmful effects of breathing molecular oxygen $(O _2)$ at elevated partial pressures. This causes hyperoxia, an excess of oxygen in body tissues.

Something that is paramagnetic means that it is weakly attracted to the poles of a magnetic field but it itself does not retain any magnetic properties once it is beyond that magnetic field. Oxygen, no matter what its state, is paramagnetic.In solid and liquid oxygen, the magnetic effect is measurable but in a gas, the molecules of oxygen possess ample energy of motion to overcome the weak magnetic influence. 

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

Which of the following plays a very important role in the oxygen cycle?

  1. Birds

  2. Animals

  3. Plants

  4. Soil
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Plants plays a very important role in the oxygen cycle as plants create the majority of oxygen we breathe through the process of photosynthesis. In this process plants use $CO _2,$ sunlight and water to create energy. In this process they also create oxygen which they release into the air.

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

Plants also consumes ________ for respiration.

  1. Carbon dioxide

  2. Oxygen

  3. Nitrogen

  4. Both A and B
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Plants also consume oxygen for respiration.


At night, when photosynthesis can’t take place, plants continue to consume oxygen but they don’t release any back into the atmosphere.


As the amount of oxygen consumes by the plants is very low during respiration so it doesn't effect the oxygen levels of the atmosphere.


Hence the correct option is B.

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.