The approximate mass of NH₄Cl present initially in the bulb is — States of Matter and Gaseous State Chemistry Question

💡 Solution & Explanation

At 600 K, He pressure doubles to $228 \text{ mm Hg}$. Pressure from decomposed gases = $908 - 228 = 680 \text{ mm Hg}$. Decomposition forms equal moles of NH₃ and HCl, so $P_{NH3} = 340 \text{ mm Hg}$. $n_{NH3} = 0.01 \times (340/228) = 0.0149 \text{ mol}$. Mass of NH₄Cl = $0.0149 \times 53.5 \approx 0.8 \text{ g}$. Therefore, correct answer is A.