Question

The value of van der Waals constant ' a ' for gases \( {O}_2 \), \( {N}_2 \), \( {NH}_3 \), and \( {CH}_4 \) are 1.360, 1.390, 4.170, and 2.253 L\(^2\)atm/mol\(^2\) respectively. The gas which can most easily be liquefied is:

• A. \( {O}_2 \)
• B. \( {N}_2 \)
• C. \( {NH}_3 \)
• D. \( {CH}_4 \)

Hint:

The larger the van der Waals constant \( a \), the stronger the intermolecular forces and the more easily the gas can be liquefied.

Answer 1

The Correct Option is C

Step 1: The van der Waals constant ' a ' indicates the strength of intermolecular forces in a gas. The higher the value of \( a \), the stronger the intermolecular forces, and the easier it is for the gas to be liquefied.
Step 2: Among the gases given, \( {NH}_3 \) has the highest value of \( a = 4.170 \), indicating the strongest intermolecular forces.
Step 3: Therefore, \( {NH}_3 \) can most easily be liquefied compared to the other gases.