# The solubility of salt at 30$^{\large\circ}$C is 50. Calculate the weight of water required to prepare a saturated solution containing 90g of salt.

Solubility (S) = 50
Amount of salt ($w_1$) = 90g
We know that,
Solubility (S) =$\large\frac{w_1}{w_2}$$\times 100----(1) Substituting the above values in equation (1), we get Weight of water (solvent)=w_2=\large\frac{100w_1}{S}=\frac{100\times 90}{50}$$=180g$
Therefore, the weight of water required to prepare the solution is 180g.
Hence (A) is the correct answer.