(JEE Advanced 2015) A student prepares a solution by dissolving of in of water. Which of the followi — Mole Concept and Some Basic Concepts of Chemistry Chemistry Question

💡 Solution & Explanation

$\text{Molality} = 1\text{ mol}/1\text{ kg} = 1\text{ m}$. <br>$\chi_{solute} = 1 / (1 + 1000/18) = 1/56.55 \approx 0.0177$. <br>$\text{Moles } Na^+ = 2 \times 1 = 2$. <br>$\text{Mass} = 1000 + 142 (MW \text{ of } Na_2SO_4) = 1142\text{ g}$.