State the information conveyed by the following equation.

Zn(s) + 2HCl (aq) ⟶ ZnCl₂ (aq) + H₂↑

The given equation tells us:

1. About the reactants involved and the products formed as a result of the reaction and their state. Zinc (Zn) and Hydrochloric acid (HCl) are the reactants. Zinc is in solid state and HCl is in aqueous solution state. The product Zinc Chloride (ZnCl₂) is also in aqueous solution state and Hydrogen is in gaseous state.
2. About the number of molecules of each substance taking part and formed in the reaction. Here one molecule of Zinc and two molecules of Hydrochloric acid react to give one molecule of Zinc chloride and one molecule of Hydrogen gas.
3. About chemical composition of respective molecules. For example, one molecule of Zinc chloride contains one atom of Zinc and two atoms of Chlorine.
4. About molecular mass; that 65 parts by weight of Zinc reacts with 73 parts by weight of Hydrochloric acid to produce 136 parts by weight of Zinc chloride and 2 parts by weight of Hydrogen.
   $\underset{65}{\text{Zn}}\text{(s)} + \underset{73}{\text{2HCl}}\text{(aq)} \longrightarrow \underset{136}{\text{ZnCl}$2}\text{(aq)} + \underset{2}{\text{H}2}\uparrow
5. 65 g of Zinc on treatment with 73 g of HCl, will produce 22.4 litres of hydrogen gas at S.T.P.
6. It also proves the law of conservation of mass. According to the above equation, 138 gram of reactants are producing 138 gram of products.