Sodium peroxide reacts with water to produce sodium hydroxide (NaOH) and hydrogen peroxide ( H2O2) aqueous solution. Product solution will be a strong alkaline solution due to occurrence of NaOH.
This reaction is occurred as protecting oxidation numbers of each elements. So this reaction is not a redox reaction (oxidation and reduction reaction).
NaOH is a strong alkaline solution and H2O2 is a very good disinfectant used in the houses.
Na2O2 + 2H2O = 2NaOH + H2O2
Due to not a redox reaction, balancing this reaction is easy than redox reaction.
See how reaction of NaOH and Cl2 redox reaction is balanced step by step.Inspection method is used to balance the reaction. First, write the reaction with reactants and products in the left side and right side respectively.
Na2O2 + H2O = NaOH + H2O2
There are two sodium atoms in the left of the reaction. But only one sodium atom in the right. So make two NaOH in the right side.
Na2O2 + H2O = 2NaOH + H2O2
Now, there is three oxygen atoms in the left side. But, in the right side, there are four oxygen atoms. To balance number of oxygen atoms, have to add oxygen to left side. So make two H2O in the left.
Na2O2 + 2H2O = 2NaOH + H2O2
Number of hydrogen atoms are balance now. No need to add more hydrogen atoms to either side. Now, we have obtained the balanced equation.
You know, sodium is a very reactive material and reacts with oxygen to produce sodium oxide. But with a oxygen gas stream, sodium peroxide ( Na2O2 ) is given as the product.
Add produced Na2O2 to distilled water to produce NaOH and H2O2 aqueous solution.
Reaction between Na2O2 and H2O will produce H2O2 and NaOH as products. You know hydrogen peroxide decomposes to oxygen and water. What is the effect of NaOH on decomposition of H2O2?
So produced H2O2 will decomposes to water and oxygen very quickly.
H2O2 can be prepared by adding water to potassium superoxide.
Potassium super oxide (KO2) reacts with water to produce potassium hydroxide (KOH), H2O2 and O2. This reaction is a redox reaction because oxidation number of oxygen is changed during the reaction.
Questions
Both Na2O2 and Na2O produce NaOH as a product with water. But when Na2O2 dissolves in water, H2O2 is given. So we have to check the presence of H2O2 in two solution. In one solution, there will be H2O2.
Na2O2 + H2O = NaOH + H2O2
Na2O + H2O = 2NaOH
Products are wrong in your this equation. OXygen gas is not released in this reaction. When sodium peroxide reacts with water, sodium hydroxide and hydrogen peroxide are given as products. Correct equation is written below from words.
sodium peroxide + water = sodium hydroxide + hydrogen peroxide
You know sodium always forms +1 oxidation state. So use algebra equation to find oxidation number of oxygen in Na2O2.
Summation of oxidation numbers of all atoms = 0
(+1)*2 + x*2 = 0
x = -1
hydrogen peroxide does not react with sodium hydroxide. But sodium hydroxide increases the decomposition rate of hydrogen peroxide to water and oxygen gas.
Peroxide ion is O22- which has a -2 negative charge. Sodium always form +1 oxidation number in compounds. So when chemical formula is written for sodium perioxide, it is Na2O2.
