The density of 20% (w/w) aqueous NaOH solution is 1.20 g/ml. What is the mole fraction of water?

Q. Calculate mole fraction of solute if molarity of solution is 20% ($\frac{W}{W}$) aqueous solution of NaOH.

Q. Aqueous solution of $NaOH$ is marked $10\%\left(w/w\right).$ The density of the solution is $1.070{gcm}^{-3}$ Calculate:
(i) molarity

Q. The mole fraction of solute in 10% (w/w) aqueous NaOH solution is:

Q. A $300g$, $30\%$ (w/w) NaOH solution is mixed with $500g$ $40\%$ (w/w) $NaOH$ solution. What is $\%$ (w/v) $NaOH$, If density of final solution is $2g/ml$.

Q. An aqueous solution of sodium chloride is marked $10$% $\left(\frac{w}{w}\right)$ on the bottle. The density of the solution is $1.071gm{l}^{-1}.$ What is its molality and molarity? Also, What is the mole fraction of each component in the solution?