Question

a liquid solvent is added to a flask containing an insoluble solid. the total volume of the solid and liquid together is 93.0 ml. the liquid solvent has a mass of 23.4 g and a density of 0.865 g/ml. determine the mass of the solid given its density is 2.75 g/ml.

Explanation:

Step1: Calculate volume of liquid

Use density formula $
ho=\frac{m}{V}$, so $V_{liquid}=\frac{m_{liquid}}{
ho_{liquid}}$.
$V_{liquid}=\frac{23.4\ g}{0.865\ g/mL}\approx27.05\ mL$

Step2: Calculate volume of solid

$V_{solid}=V_{total}-V_{liquid}$.
$V_{solid}=93.0\ mL - 27.05\ mL = 65.95\ mL$

Step3: Calculate mass of solid

Use density formula again, $m_{solid}=
ho_{solid}\times V_{solid}$.
$m_{solid}=2.75\ g/mL\times65.95\ mL\approx181\ g$

Answer:

$181\ g$