$36 \ g$ of water and $828 \ g$ of ethyl alcohol form an ideal solution. The mole fraction of water in it is:

The molarity of the solution obtained by mixing $480 \, mL$ of $1.5 \, M$ solution with $500 \, mL$ of $1.2 \, M$ solution is ........ $M$.

$300 \ g$ of $25\%$ solution and $400 \ g$ of $40\%$ solution are mixed by weight. Calculate the percentage of the solute by weight in the final mixture. (in $\%$)

What is the mole fraction of water in a spirit sample containing $92\%$ ethyl alcohol by mass?

Molality of $30 \% \ w/w$ aqueous solution of $NaOH$ is . . . . . . . (in $m$)

$8 \ g$ of $NaOH$ is dissolved in $18 \ g$ of $H_2O$. Mole fraction of $NaOH$ in solution and molality (in $mol \ kg^{-1}$) of the solution respectively are