JAMB Chemistry 1985 Question 5

In an experiment, which of the following observations would suggest that a solid sample is a mixture? The

1. A.solid can be ground to a fine powder
2. B.density of the solid is 2.25 g dm⁻³
3. C.solid begins to melt at 573 K but is not completely melted until 648 K
4. D.solid absorbs moisture from the atmosphere and turns into a liquid
5. E.solid melts at 300 K.