Question

How can we determine whether solid , liquid or gas in aonic equation

Answer 1

With experience you know may of them. For example, you know that aluminum is a solid, hydrogen and oxygen are gases, and water is a liquid at room temperature. If you don't know you can always look up the melting point and the boiling point of the compound. Even then, however, it's a guessing game, especially if you don't know the temperature of the reaction.