What type of solution is obtained from an amalgam of mercury with sodium?

The molality of an aqueous solution of any solute having a mole fraction of $0.25$ is . . . . . . . (in $m$)

If the mole fraction of $H_2SO_4$ in an aqueous solution of $H_2SO_4$ is $0.1$,then the molality of the solution will be ......... $m$.

If the density of a $5 \ M$ solution of $KCl$ is $1.26 \ g \ mL^{-1}$,then find the molality of the solution. (molecular mass of $KCl = 74.55 \ g \ mol^{-1}$) (in $m$)

Calculate the $\% \, w/w$ of a solution formed by dissolving $20 \, g$ of solute in $200 \, g$ of water.

Calculate the molarity of $NaOH$ in the solution prepared by dissolving $4 \,g$ of it in enough water to form $250 \,mL$ of the solution. (in $,M$)