Question

In a mixture of $A$ and $B$, components show negative deviation when :

• A. $A-B$ interaction is stronger than $A-A$ and $B-B$ interaction
• B. $A-B$ interaction is weaker than $A-A$ and $B-B$ interaction
• C. $△V_{\mathrm{mix}}<0$
• D. $\Delta V_{\text{mix }}=0,\Delta S_{\text{mix }}>0$

Answer 1

Answer: (C)

In a mixture component $A$ and component $B$ Shows negative Deviation as, $△$ Vmixing $<0$.
i.e. For Negative Deviation, $△$ Vmixing=-ve , $△$ Hmixing $=-ve$
Because, the forces of attraction between components $A$ and $B$ is greater.
Due to that the tendency of escaping of molecules $AB$ from solution becomes less than that of pure liquids. A-B attractive forces is greater than A-A and B-B attractive forces.