Question

Which gas will diffuse the fastest under identical conditions of temperature and pressure?

• A. Oxygen (O\textsubscript{2})
• B. Nitrogen (N\textsubscript{2})
• C. Ammonia (NH\textsubscript{3})
• D. Hydrogen (H\textsubscript{2})

Answer 1

The Correct Option is D

Step 1: Use Graham’s law of diffusion: \[ \text{Rate of diffusion} \propto \frac{1}{\sqrt{\text{Molar mass}}} \] Step 2: Compare molar masses: \begin{itemize} \item O\textsubscript{2} = 32 g/mol \item N\textsubscript{2} = 28 g/mol \item NH\textsubscript{3} = 17 g/mol \item H\textsubscript{2} = 2 g/mol \end{itemize} Step 3: Lowest molar mass = H\textsubscript{2 ⇒ fastest diffusion} \[ \boxed{\text{Hydrogen diffuses fastest}} \]