(IIT-JEE 1990) When of a hydrated salt () is heated, of anhydrous salt is left. If the molecular wei — Mole Concept and Some Basic Concepts of Chemistry Chemistry Question

💡 Solution & Explanation

$\text{Mass } H_2O = 2.46 - 1.20 = 1.26 \text{ g}$. $\text{moles } H_2O = 1.26/18 = 0.07$. $\text{moles anhydrous} = 1.20/120 = 0.01$. Ratio $H_2O : \text{Salt} = 0.07 : 0.01 = 7$. Salt with $MW=120$ is $MgSO_4$. [11]