Liquids $A$ and $B$ form an ideal solution. Which of the following statements is true?

Which condition is not satisfied by an ideal solution?

The ideal solutions formed by mixing two liquids $A$ and $B$ at $300 \ K$ in the molar ratio of $1:1$ and $1:2$ have vapour pressures of $400 \ mm$ and $350 \ mm$ respectively. At the same temperature,the vapour pressures of pure liquids $A$ and $B$ in $mm$ respectively are:

Which of the following mixtures forms an ideal solution?

Which one of the following non-ideal solutions shows negative deviation?

At $300 \ K$,the vapour pressures of $A$ and $B$ liquids are $500 \ mm \ Hg$ and $400 \ mm \ Hg$ respectively. Equal moles of $A$ and $B$ are mixed to form an ideal solution. The mole fraction of $A$ and $B$ in the vapor state is respectively: