1. Compound description ionic or molecular? 1 Compound 1 is a hard white smooth odorless solid, which is insoluble in water. If the flame from an ordinary laboratory burner is held on the solid for 10 minutes, the solid grows hot to the touch but does not soften. ionic molecular (can't decide)

2 Compound 2 is a hard light gray solid made up of clusters of cube-shaped crystals. It can easily be ground into a fine powder. If that powder is compressed to form a block, the block is an insulator. However, if the block is moistened slightly, it starts to conduct electricity much better. ionic molecular (can't decide)

3 Compound 3 is a clear liquid with a strong pleasantly fruity smell. If cooled it freezes at about −10°C. In the solid state it does not conduct electricity. ionic molecular (can't decide)

The solid that has been designated as compound 1 is difficult to really classify because, we can see that the solid only became hot when heated but does not soften. This can be an attribute of an ionic solid. However, the same solid is not soluble in water. This insolubility in water is a property of molecular solids. As a result of these, we will find it difficult to classify the solid.

Compound 2 is also difficult to decide upon because ionic solids are crystalline and can not be ground into powder. Amorphous substances can be ground into powder easily. Then, we can see that the substance does not conduct electricity in block form but does so when moistened. This means that we can not conveniently classify it as a molecular solid since molecular substances do not conduct electricity.

A molecular substance usually has a low melting and freezing point and also does not conduct electricity hence compound 3 is molecular solid.