Question

According to the following reaction, how many grams of hydrogen peroxide $\left( {{H_2}{O_2}} \right)$ are necessary to form 0.182 moles oxygen gas?
Hydrogen peroxide $\left( {{H_2}{O_2}} \right)(aq) \to water(l) + oxygen(g)$

Answer 1

Hydrogen peroxide is a highly unstable compound. It is colourless and has a sharp odour. When it is heated it decomposes into water and oxygen. It also reacts with alkali metals and hence, it is stored in a dark room to avoid direct contact with sunlight.

Complete answer:
The chemical equation is:
$\left( {{H_2}{O_2}} \right) \to {H_2}O + {O_2}$
Firstly, we should balance the equation,
We see that if we multiply $2$ with hydrogen peroxide and water, then its balanced.
Hence, the final balanced equation is:
$2\left( {{H_2}{O_2}} \right) \to 2{H_2}O + {O_2}$
Now, the number of moles ratio of hydrogen peroxide to oxygen is 2:1.
The number of moles required by hydrogen peroxide to form 0.182 moles of oxygen gas is:
= 0.182 \times 2 \\\ = 0.364 \\\
Molar mass of hydrogen peroxide
= 1 \times 2 + 16 \times 2 \\\ = 2 + 32 \\\ = 34 \\\
To find the total mass we should multiply molar mass of hydrogen peroxide with the moles
= 0.364 \times 34 \\\ = 12.376gm \\\
Hence, we need 12.376 grams of hydrogen peroxide to form 0.182 moles oxygen gas.

Note:
Hydrogen peroxide reaction acts as the best defence system for our body. The oxygen and water which is produced during the reaction comes in contact with catalase which is an enzyme in the liver. Hydrogen peroxide is produced as a product of metabolism and it can attack important biochemicals in our body. Hence, it decomposes itself to protect the body.