Question

26 Match the items in column I to those in column II

Column 1	Column 2
moving air	photosynthesis
layer in which we live	inert gas
stratosphere	water vapor
radon	protein
oxygen	smoke and fog
carbon dioxide	ozone layer
exhaled air	combustion
humidity	wind
smog	increased carbon dioxide
nitrogen	troposphere

Answer 1

(A) Moving air-(VIII) Wind

• Moving air is referred to as Wind.
• The wind is the movement of air that occurs when air from a high-pressure area moves to a low-pressure area. These winds can be pleasant and at a moderate speed, or they can be extremely powerful (as in cyclones and hurricanes).

(B) layer in which we live-(X) Troposphere

• The troposphere is the atmosphere's lowest layer.
• It is the layer where we reside.
• The wind moves take place in the layer. It also contains water vapour, which is what causes clouds.
• This is the layer in which weather changes occur.

(C) Stratosphere-(VI) Ozone layer

• The stratosphere extends from the top of the troposphere to about 50 kilometres (31 miles) above the ground.
• An ozone layer exists in the stratosphere.
• This layer's ozone molecules absorb and alter the Sun's high-energy ultraviolet (UV) light.

(D) Radon-(II) Inert gas

• An inert gas is one that does not undergo chemical reactions with other chemicals and does not generate chemical compounds.
• Inert gas elements belong to group 18.
• Helium$\left(\mathrm{He}\right)$, Neon$\left(\mathrm{Ne}\right)$, Argon$\left(\mathrm{Ar}\right)$, Krypton$\left(\mathrm{Kr}\right)$, Xenon$\left(\mathrm{Xe}\right)$, Radon$\left(\mathrm{Ra}\right)$

(E) Oxygen-(VII) Combustion

Combustion occurs in the presence of air (Oxygen)

The burning of methane releases Carbon dioxide and water.

$\underset{\mathrm{Methane}}{{\mathrm{CH}}_4\left(\mathrm{g}\right)}+\underset{\mathrm{Oxygen}}{2{\mathrm{O}}_2(\mathrm{g}})\to \underset{\mathrm{Carbon}\mathrm{dioxide}}{{\mathrm{CO}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Water}}{2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}$

(F) Carbon dioxide-(I) Photosynthesis

Photosynthesis is the process in which plants make their own food, by utilizing carbon dioxide and water in the presence of sunlight, and chlorophyll producing glucose and oxygen.

(G) Exhaled air-(IX) increased carbon dioxide

Carbon dioxide is exhaled by living organisms.

The respiratory system's function is to take in oxygen and exhales carbon dioxide. The body's cells require oxygen to carry out processes that keep us alive. Carbon dioxide is the waste product produced by the cells when they have completed all their functions.

This Carbon dioxide is utilized by plants during their photosynthesis process.

(H) Humidity-(III) Water vapour

The amount of water vapour present in the air is referred to as Humidity.

• The more humid the surrounding air is, the slower a wet object dries and vice versa.
• The amount of water vapour that the air can hold is determined by its temperature.

(I) Smog-(V) Smoke and fog

Smog is a type of pollution in the air. It's a mix of smoke and fog from many sources (water droplets suspended over the surface of the earth). Lung disorders such as bronchitis and asthma can be caused by inhalation.

(J) Nitrogen-(IV) Protein

• Amino acids, the building blocks of proteins, contain a lot of nitrogen.
• Plants obtain nitrogen through a natural process. Fertilizers, as well as animal and plant residues, add nitrogen to the soil.
• Bacteria in the soil convert the nitrogen to ammonium and nitrate, which is taken up by the plants by a process of nitrogen fixation.

Column I	Column II
(A) Moving air	(VIII) Wind
(B) layer in which we live	(X) Troposphere
(C) Stratosphere	(VI) Ozone layer
(D) Radon	(II) Inert gas
(E) Oxygen	(VII) Combustion
(F) Carbon dioxide	(I) Photosynthesis
(G) Exhaled air	(IX) increased carbon dioxide
(H) Humidity	(III) Water vapour
(I) Smog	(V) Smoke and fog
(J) Nitrogen	(IV) Protein