Question

What is the ratio of kinetic energies of 3 $g$ of hydrogen and 4 $g$ of oxygen at $T$($K$)?

• A. 12:1
• B. 6 : 1
• C. 1 : 6
• D. 24 : 1

Answer 1

The correct option is A 12:1

At same temperature,

$\frac{K{E}_1}{K{E}_2}=\frac{n_1}{n_2}$

No. of moles of hydrogen $=\frac{3}{2}=1.5$ moles

No. of moles of oxygen $=\frac{4}{32}=0.125$ moles

Thus, $\frac{K{E}_1}{K{E}_2}=\frac{1.5}{0.125}=12:1$

Hence, the correct answer is option $\text{A}$.