In which of the following liquid pair, there is contraction in volume on mixing? — Solutions and Colligative Properties Chemistry Question

💡 Solution & Explanation

Volume contraction ($\Delta V_{mix} < 0$) occurs in non-ideal solutions exhibiting negative deviation from Raoult's law, where intermolecular interactions become stronger upon mixing. Chloroform and benzene ($\text{CHCl}_3 + \text{C}_6\text{H}_6$) show a negative deviation. Water forms very strong ion-dipole and hydrogen bonds with strong acids like HCl and $\text{HNO}_3$, causing significant contraction. Therefore, correct answer is A,B,C.