Molarity of $4\%$ $NaOH$ solution is ......... $M$.

If the mole fraction of ethanol in a solution formed by mixing $x \, g$ of water and $69 \, g$ of ethanol is $0.6$,then $x =$ ...... $g$.

If a solution is $98\% \ H_2SO_4$ by weight and has a density of $1.8 \ g/mL$,its molarity is ....... $M$.

Two solutions of a substance are mixed as follows: $480 \ mL$ of $1.5 \ M$ first solution + $520 \ mL$ of $1.2 \ M$ second solution. The molarity of the final solution will be ............. $M$.

If $18 \ g$ of glucose $(C_6H_{12}O_6)$ is present in $1000 \ g$ of an aqueous solution of glucose,it is said to be ......... $molal$.

The volume of water added to $500 \ mL$ of $0.5 \ M \ NaOH$ solution so that its strength becomes $10 \ mg \ mL^{-1}$ will be .......... $mL$.