Sodium peroxide
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Sodium peroxide is a chemical compound made of sodium and peroxide ions. Its chemical formula is Na2O2. The molar mass is around 77.98 g/mol (anhydrous). It usually forms the octahydrate compound when hydrated. It appears as a yellow to white powder (anhydrous) or just white powder (octahydrate). It is a strong base.
Formation and reactions of sodium peroxide
It is made when sodium metal reacts with excess oxygen when heated to first make sodium oxide then to sodium peroxide.
- The first step balanced chemical equation is:
- 4Na + O2 → Na2O
- The second step balanced chemical equation is:
- 2Na2O + O2 → 2Na2O2
It can be also made (the octahydrate form) when sodium hydroxide reacts with hydrogen peroxide (and some water).
- The balanced chemical equation is:
- 2NaOH + H2O2 + 6H2O → Na2O2 · 8H2O
It hydrolyzes in water to make sodium hydroxide and hydrogen peroxide or oxygen depending on the temperature.
- The balanced chemical equation (in cold water) is:
- Na2O2 + 2H2O → 2NaOH + H2O2
- While the balanced chemical equation (in hot water) is:
- 2Na2O2 + 2H2O → 4NaOH + O2