What are the values of $\Delta H_{mix}$ and $\Delta V_{mix}$ for an ideal solution?

Given:
Solution $A$: Phenol and aniline
Solution $B$: Chloroform and acetone
Which of the following is correct as per Raoult's law?

The boiling point of an equimolar ideal solution of hexane $(C_6H_{14})$ and heptane $(C_7H_{16})$ is $80 \ ^oC$. What is the boiling point of a mixture of hexane and heptane containing equal mass of both? The boiling points of pure hexane and pure heptane are $69 \ ^oC$ and $98 \ ^oC$ respectively.

Which of the following mixtures does not show positive deviation from Raoult's law?

Explain non-ideal solutions and the occurrence of positive and negative deviations in non-ideal solutions.

Liquids $A$ and $B$ form an ideal solution for all compositions of $A$ and $B$ at $25^{\circ} C$. Two such solutions with $0.25$ and $0.50$ mole fractions of $A$ have total vapor pressures of $0.3 \ bar$ and $0.4 \ bar$,respectively. What is the vapor pressure of pure liquid $B$ in $bar$?