The total volume of a solid and liquid together is 86.0 mL. The liquid solvent has a mass of 35.3 g & density of 0.865 g/mL. What's the mass of the solid given its density, 3.00 g/mL.

Answer 1

Hello, Kailee,

I summarized what we know:

Note: I'll Ignore significant figures for the moment, but I note that the density of the solid has only one sig fig.

Since we have the solid mass and it's density, we can calculate the solvent volume by dividing it's mass by it's density: = 35.3 g/0.865 g/ml.

The grams cancel and the ml moves to the top, so the resulting unit is ml, which is 40.81 ml.

Since we have a total volume of 86 ml, and 40.81 ml is the solvent, the total volume of the solid is the difference: 86 ml - 40.81 ml = 45.2 ml.

We have the density of the solid as 3g/ml. Since we have 45.20 ml, we multiply it by the density: 45.2 ml * 3 g/ml. The ml cancels and we are left with grams. This calculates to 135.6 grams.

I ignored sig figs, but if we look at the values of the original data, the density of the solid only has one digit, so the sig figs is set to one, which seems way too short for this type of problem.

I hope this helps,

Bob