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: Understanding the Concept:
The question asks to arrange the given gases in order of their abundance in the Earth's dry atmosphere, from the least abundant to the most abundant.

Step 3: Detailed Explanation:
The approximate concentrations of these gases in dry air are:
\[\begin{array}{rl} \bullet & \text{(C) Nitrogen (N\(_2\)): ~78.08%} \\ \bullet & \text{(A) Oxygen (O\(_2\)): ~20.95%} \\ \bullet & \text{(D) Argon (Ar): ~0.93%} \\ \bullet & \text{(B) Carbon dioxide (CO\(_2\)): ~0.04% (variable)} \\ \bullet & \text{(E) Neon (Ne): ~0.0018%} \\ \end{array}\] Arranging these in increasing order of concentration (from smallest to largest percentage):
Neon (E) \textless Carbon dioxide (B) \textless Argon (D) \textless Oxygen (A) \textless Nitrogen (C).

Step 4: Final Answer:
The correct order of gases in increasing concentration is: (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%). This corresponds to the sequence (E), (B), (D), (A), (C).