Question

Who do we balance a chemical equation​

Answer 1

I think you meant how?

Step-by-step explanation:

but always you balance a chemical equation by looking at how many atoms you have for each element. For example we have the chemical equation Na + Cl2----> NaCl

so there's 1 Na atom

there's 2 Cl atoms

and for the product side

there's 1 Na atom

there's 1 Cl atom

TO BALANCE THIS you have to make the reactants side equals the product side by ADDING COEFFICIENTS.

so it would be 2Na + Cl2 ---> 2NaCl

Answer 2

We have to balance chemical equations because you need to satisfy the law of conservation of matter. That states that matter cannot be produced or destroyed in a closed system. The law of conservation of mass governs the balancing of a chemical equation.