Which of the following statements describes the difference between a mixture and a pure substance?
A. A mixture tends to be homogeneous, while a pure
substance tends to be heterogeneous.
B. A mixture has a specific melting point, while the
melting point of a pure substance can vary.
C. The density of a mixture can change with temperature,
but the density of a pure substance cannot change.
D. The composition of a mixture can vary from sample to
sample, but the composition of a pure substance is
always the same.