For a certain liquid mixture, it is observed that the process of mixing is exothermic ( H_ mix < 0 ) and is accompanied by a contraction in volume ( V_ mix < 0 ). Which of the following pairs of liquids exhibits this behaviour?

Step-by-step solution

The conditions H_ mix Among the given options, a mixture of chloroform and diethyl ether shows a negative deviation due to the formation of intermolecular hydrogen bonds between the hydrogen atom of chloroform and the oxygen atom of diethyl ether. Ethanol and water, as well as carbon disulfide and acetone, show positive deviations ( H_ mix > 0 , V_ mix > 0 ). Benzene and toluene form a nearly ideal solution ( H_ mix = 0 , V_ mix = 0 ). Answer: Chloroform and Diethyl ether