Question

what are the drawbacks of a chemical equation? illustrate with an example

Answer 1

It does not mention the state of the substances. So (s) for solid, (l) for liquid, (g) for gas and (vap) for vapor may be added.
The reaction may or may not be complete. Equation does not reveal it.
It does not give any information regarding the speed of the reaction.
It does not give the concentration of the substances. In some cases, terms like diluted and concentrated may be added.
It does not give the conditions of temperature, pressure, catalyst, etc. This is overcome by mentioning these above or below the arrow e.g.,

It does not give any idea about colour changes, which has to be mentioned separately.

It does not give any indication regarding the production or absorption of heat. This is mentioned separately.

Answer 2

The drawbacks of chemical equation are:-

1)Physical states if reactants and products.
2)Heat changes.
3)Extent if reaction.
4)Mechanism of reaction.
5)Evolution of gas.
6)Rate of reaction.

The drawbacks are removed by :-
1)Indication of physical states by symbols.
2)Conditions necessary written along the arrows.
3)Rate of reaction indicated by writting slow or fast with products.
4)Heat changes are written by writing +QKJ or -QKJ.

Examples :-
1)It does not tell us about through which the reaction proceeds.
2)It does not tell us the physical chanfes like colour etc.

Hope it helped....