A schematic representation of any chemical equation with the help of symbols and formulae of various species involved is known as a chemical equation. The reactants are written on the left hand side with a plus sign between them . Similarly,the products are written on the right hand side with a plus sign between them. The arrowhead points towards the products, and shows the direction of the reaction.the chemical equations can be made more informative in 3 ways: 1. By indicating the physical states of the reactants and products. 4 states involved are solid,liquid,aqueous solution,liquid. This way the equation becomes more informative because it tells the physical states of the various substances involved in it. 2. By indicating the heat changes taking place in the reactin 3. By indicating the conditions in which the reaction takes place