Chemical equations can be made more informative by the

following characteristics:

Physical state

There are three different states which are solid, liquid and gaseous. If the substance exists in solid state, it is represented by (s).

If the substance exists in aqueous state, it is represented by (aq).

If the substance exists in gaseous state, it is represented by (g).

For example:

Evolution of gas

If the gas is liberated in a reaction, it is indicated by an arrow upward

and its physical state is shown by (g).

For example:

Zn(s) + H₂SO₄(aq) → ZnSO₄(aq) + H₂(g)↑