Answer
Yes, the densities match.
Work Step by Step
This question is basically a density problem. We are told that a compound is unlabeled, and believed to be benzene. We have to prove whether or not it is benzene. We are given the density of benzene, .8787 g/mL, the mass of the substance 21.95 g, and the volume, 25 mL. Now we have to use the density formula, where density=mass/volume. When you substitute in the givens, the density of the unknown compound is .878 g/ml. This is a small enough difference that we can conclude the unknown to be benzene.
