Question

the solubility of salt is 35.7 g per 100 g of water at 25.0°c. to find the percentage of salt in a saturated solution, which concentration calculation should be used?
volume percent
volume mass percent
mass percent
mass volume percent

Explanation:

To determine the percentage of salt in a saturated solution, we analyze the given data: solubility is 35.7 g (mass of salt) per 100 g (mass of water).

• Volume percent involves volumes of solute and solution, but we have masses, so this is not suitable.
• Volume - mass percent involves volume of solute and mass of solution, which is not the case here as we have masses of both solute and solvent.
• Mass percent is calculated as $\frac{\text{mass of solute}}{\text{mass of solution}}\times100\%$. The mass of the solution is the sum of the mass of the solute (salt) and the mass of the solvent (water). Here, we have the mass of the solute (35.7 g) and the mass of the solvent (100 g), so we can find the mass of the solution (35.7 g+100 g) and then use the mass - percent formula.
• Mass - volume percent involves mass of solute and volume of solution, but we are given masses of solute and solvent, not volume of solution.

So, the appropriate concentration calculation is mass percent.

Answer:

C. mass percent