Question

Balance the following skeletal equations.

$\mathrm{Al}+\mathrm{HCl}\to {\mathrm{AlCl}}_3+{\mathrm{H}}_2$

Answer 1

Balanced chemical equation -

• A chemical equation is said to be balanced if the number of atoms of each element on the left-hand side is equal to the number of atoms present on the right-hand side.
• In order to balance a chemical equation, it is required to know what are reactants that are taking part in a chemical reaction and what are products will be formed.

Balancing a chemical equation- Using Hit by trial method

$\mathrm{Al}+\mathrm{HCl}\to {\mathrm{AlCl}}_3+{\mathrm{H}}_2$

Elements	Number of atoms on reactant side	Number of atoms on product side
Al	1	1
H	1	2
Cl	1	3

1. To balance H, put coefficient 2 on the left-hand side. $\mathrm{Al}+2\mathrm{HCl}\to {\mathrm{AlCl}}_3+{\mathrm{H}}_2$
2. Now, to balance Cl, put coefficient 3 before $\mathrm{HCl}$ and 2 before ${\mathrm{AlCl}}_3$. $\mathrm{Al}+6\mathrm{HCl}\to 2{\mathrm{AlCl}}_3+{\mathrm{H}}_2$
3. Now, to balance Al, put coefficient 2 before Al. $2\mathrm{Al}+6\mathrm{HCl}\to 2{\mathrm{AlCl}}_3+{\mathrm{H}}_2$
4. Hence, the balanced chemical equation is $2\mathrm{Al}+6\mathrm{HCl}\to 2{\mathrm{AlCl}}_3+{\mathrm{H}}_2$