How would you balance the following equation:
${\mathrm{H}}_2{\mathrm{O}}_2\to {\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2$

Balancing the chemical equation

• Given the chemical equation is
  $\underset{\mathrm{Hydrogen}\mathrm{peroxide}}{{\mathrm{H}}_2{\mathrm{O}}_2\left(\mathrm{l}\right)}\to \underset{\mathrm{Water}}{{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}+\underset{\mathrm{Oxygen}}{{\mathrm{O}}_2\left(\mathrm{g}\right)}$
• To balance the given chemical equation we need to verify the Law of Conservation of Mass
• Write down the number of atoms

Write down the number of atoms of each element present on both reactant and product side.

Atom	Reactant side	Product side
H	2	2
O	2	3

• Add coefficients to balance the mass in a chemical equation
  Add 2 molecules of Hydrogen peroxide (${\mathrm{H}}_2{\mathrm{O}}_2$) and 2 molecules of Water (${\mathrm{H}}_2\mathrm{O}$).
• This reaction is a decomposition reaction of Hydrogen peroxide into Water and Oxygen.
• The balanced chemical equation is: $\underset{\mathrm{Hydrogen}\mathrm{peroxide}}{2{\mathrm{H}}_2{\mathrm{O}}_2\left(\mathrm{aq}\right)}\to \underset{\mathrm{Water}}{2{\mathrm{H}}_2\mathrm{O}}\left(\mathrm{l}\right)+\underset{\mathrm{Oxygen}}{{\mathrm{O}}_2\left(\mathrm{g}\right)}$