Question

Major component of the atmosphere on Venus and Mars planets is
(a) Carbon-dioxide
(b) Oxygen
(c) Hydrogen
(d) Water Vapour

Answer 1

The major component of the atmosphere on Venus and Mars is a colorless gas with a density of about $53\%$ higher than that of dry air. It is the most significant long-lived greenhouse gas in Earth’s atmosphere. In its solid-state, it is called dry ice.

Complete answer:
The major component of the atmosphere found on Venus and Mars is carbon dioxide (95-97%) and as such it does not support life. Carbon dioxide is an important gaseous component of the environment. It is fixed by the green plants by the process of photosynthesis. It is released during expiration by the process of respiration. Venus is the twin planet to earth as it has the atmosphere. It is the hottest planet as it is made up of $97\%$ carbon dioxide. The atmosphere of Venus consists of carbon dioxide, with clouds of sulfuric acid droplets. The thick atmosphere traps the Sun's heat, resulting in surface temperatures higher than 470 degrees Celsius. The atmosphere has many layers with different temperatures. The atmosphere of Mars is the layer of gases surrounding Mars. It is primarily composed of carbon dioxide, molecular nitrogen, and argon. It also contains trace levels of water vapor, oxygen, carbon monoxide, hydrogen, and other noble gases. The atmosphere of Mars is much thinner than Earth’s.

Additional Information:
- The atmosphere of Venus has a huge troposphere. Within the troposphere, the gas is heated from below and circulates slowly, rising near the equator and descending over the poles.
- Nitrogen is the second most common gas in the atmosphere of Venus.
- Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, being larger than only Mercury.
So, the correct answer is '(a) Carbon dioxide'.

Note:
- Mars is a terrestrial planet with a thin atmosphere. The days and seasons are comparable to those of Earth, because the rotational period, as well as the tilt of the rotational axis relative to the ecliptic plane, is similar.
- Venus is the second planet from the Sun. It is named after the Roman goddess of love and beauty.
- Venus has a rotation period of 243 Earth days, it takes longer to rotate about its axis than any other planet in the Solar System.