In this Revision Bite we will look at physical changes and then geological changes. The geological changes are only in this Revision Bite. A physical change in a substance does not involve a chemical change. When a substance changes its state its mass will remain unchanged. For example, 500g of solid lead will be 500g of liquid lead when it is melted.
Different substances have different melting points, boiling points and densities.
Click here to see a table showing the melting points, boiling points and densities of different substances. Here is a method for working out if a substance is a solid, liquid or gas at room temperature. This question is often asked in your tests. Label it solid below melting point, liquid between the melting and boiling points and gas above the boiling point. Boiling point Bromine is a liquid at room temperature.