Question

A solution is made by dissolving 4.87 g of potassium nitrate to a final volume of 86.4 mL solution. What is the weight/volume of the solute?

Answer 1

We assume, (i) that the solvent is water, and (ii) that dissolution occurs without change in volume.

Explanation:

So given the standard density of water, the mass of the solution is simply, `(4.87+86.4)*g`. For the solution `"mass"/"volume"="density"(rho)` `=` `((4.87+86.4)*g)/(86.4*mL)`, slightly over `1*g*mL`. Because nitrate salts are soluble stuff, you could get significantly higher solution densities if you dissolved more salt (volume change would be fairly negligible).