Which of the following atmospheric pollutants acts primarily as a greenhouse gas by absorb… — JAMB UTME

Which of the following atmospheric pollutants acts primarily as a greenhouse gas by absorbing terrestrial infrared radiation, rather than destroying stratospheric ozone through catalytic radical chain reactions?

Carbon(IV) oxide ( $CO_2$ )Answer
B
Dichlorodifluoromethane ( $CF_2Cl_2$ )
C
Nitrogen(II) oxide ( $NO$ )
D
Trichlorofluoromethane ( $CCl_3F$ )

Answer

Carbon(IV) oxide (

CO_2

)

Carbon(IV) oxide (

CO_2

) functions primarily as a greenhouse gas by absorbing outgoing terrestrial infrared radiation and re-radiating it back toward the Earth's surface. Unlike chlorofluorocarbons or nitric oxide,

CO_2

does not photolytically generate free radicals that decompose stratospheric ozone.

Step-by-Step Solution

Analyze the environmental mechanism described in the stem.

The mechanism specifies absorbing re-radiated longwave infrared radiation from the Earth's surface (greenhouse effect) in the troposphere, rather than catalytic free radical destruction of ozone (

O_3

) in the stratosphere.

Greenhouse gases retain heat energy in the lower atmosphere, whereas ozone-depleting substances release reactive species that decompose stratospheric ozone.

Evaluate the chemical behavior of each listed atmospheric gas.

Carbon(IV) oxide (

CO_2

) is a major greenhouse gas responsible for trapping infrared heat. Chlorofluorocarbons (

CF_2Cl_2

and

CCl_3F

) and nitrogen(II) oxide (

NO

) act as catalysts in stratospheric ozone depletion.

Halogen radicals (

Cl^\bullet

) cleaved from CFCs by UV light and nitric oxide radicals (

NO

) catalyze ozone decomposition, whereas

CO_2

does not react with stratospheric ozone.

Key Concept

Distinguishing greenhouse gases (infrared radiation absorbers) from ozone-depleting substances (free radical catalysts).

Estimated Time:1m 0s

Question

Answer

Step-by-Step Solution

Key Concept

Common Mistakes

Topics

More questions from this topic