Question

Match List-I (Gas) with List-II (Atomic Weight)
 

List-I (Gas)	List-II (Atomic Weight)
A. Argon	II. 40
B. Krypton	IV. 86
C. Carbon dioxide	III. 44
D. Ozone	I. 48

• A. A-II, B-I, C-III, D-IV
• B. A-II, B-III, C-I, D-IV
• C. A-II, B-IV, C-III, D-I
• D. A-III, B-IV, C-I, D-II

Hint:

Quick molecular mass recall for atmospheric gases: \[ \text{CO}_2: 44, \quad \text{O}_3: 48, \quad \text{N}_2: 28, \quad \text{O}_2: 32, \quad \text{Ar}: 40, \quad \text{Kr}: 84 \] These are frequently asked in atmospheric science and physical chemistry questions.

Answer 1

The Correct Option is C

Concept: Molecular (molar) mass is calculated using atomic masses of constituent elements:
• For a monatomic element: molar mass \(=\) atomic mass of element.
• For a molecule: molar mass \(=\) sum of atomic masses of all atoms.
• Key atomic masses: C=12, O=16, Ar=40, Kr=84.

Step 1: Calculate molar mass of Argon (Ar).
Argon is a monatomic noble gas: \[ M_{\text{Ar}} = 40 \text{ g/mol} \;\Rightarrow\; II \]

Step 2: Calculate molar mass of Krypton (Kr).
Krypton is a monatomic noble gas: \[ M_{\text{Kr}} = 84 \approx 86 \text{ g/mol (nearest option)} \;\Rightarrow\; IV \]

Step 3: Calculate molar mass of Carbon dioxide (CO\(_2\)).
\[ M_{\text{CO}_2} = 12 + 2 \times 16 = 44 \text{ g/mol} \;\Rightarrow\; III \]

Step 4: Calculate molar mass of Ozone (O\(_3\)).
\[ M_{\text{O}_3} = 3 \times 16 = 48 \text{ g/mol} \;\Rightarrow\; I \]

Step 5: Confirm the final match.
A-II, B-IV, C-III, D-I \(\Rightarrow\) Option (3).