Question

Arrange the following gases in increasing order of their concentrations in the Earth's atmosphere.
(A) Oxygen
(B) Carbon dioxide
(C) Nitrogen
(D) Argon
(E) Neon
Choose the correct answer from the options given below:

• A. (B), (E), (D), (A), (C)
• B. (E), (D), (B), (A), (C)
• C. (C), (A), (D), (B), (E)
• D. (E), (B), (D), (A), (C)

Hint:

For atmospheric composition, remember the top four gases in order: Nitrogen (>78%), Oxygen (~21%), Argon (~1%), and Carbon Dioxide (~0.04%). All other gases are present in much smaller trace amounts.

Answer 1

The Correct Option is D

Step 1: Objective: Arrange the given gases by their abundance in Earth's dry atmosphere, from least to most abundant.

Step 3: Data and Analysis: Approximate concentrations of gases in dry air are:

• (C) Nitrogen (N\(_2\)): ~78.08%
• (A) Oxygen (O\(_2\)): ~20.95%
• (D) Argon (Ar): ~0.93%
• (B) Carbon dioxide (CO\(_2\)): ~0.04% (variable)
• (E) Neon (Ne): ~0.0018%

Ordered by increasing concentration: Neon (E) < Carbon dioxide (B) < Argon (D) < Oxygen (A) < Nitrogen (C).

Step 4: Conclusion: The gases in order of increasing concentration are: (E) Neon (~18 ppm), (B) Carbon dioxide (~400 ppm), (D) Argon (~9300 ppm or 0.93%), (A) Oxygen (~20.95%), and (C) Nitrogen (~78.08%). The sequence is (E), (B), (D), (A), (C).