What does the chemical formula of a compound indicate? Use an example to illustrate your points.
Chemical properties describe the ability of a substance to undergo particular chemical changes. Chemical properties can only be observed when a substance undergoes a change in composition. Physical properties can be observed without altering the composition of a substance. The ability of iron to rust is a chemical property of iron. The fact that iron is a solid at room temperature is a physical property of iron.
Isotopes of the same element have different mass numbers.
What does the number 84 in the name krypton-84 represent?
the mass number