Question

The approximate mass of $$H_2{O}_2$$ present in 200ml of 100 volume $$H_2{O}_2$$ in grams is:
A.3
B.30
C.60
D.6

Answer 1

Hint: The concentration or amount of solute which is present in the total solution is referred to as the strength. We can define volume strength similarly as the volume of oxygen produced by one litre of hydrogen peroxide. Basically, we are preparing oxygen from hydrogen peroxide.
Formula used:
 $$numberofmoles={\displaystyle \frac{totalvolumeliberated}{volumeatNTP}}$$

Complete step by step answer:
Volume strength refers to the volume of oxygen gas liberated from one volume of $$H_2{O}_2$$ ​ solution (at $$0^{0}C$$ and 1 atm.). 100 volume hydrogen peroxide solution means that on reduction, the oxygen released will be 100 times the volume of the sample at NTP.
 $$2H_2{O}_2\to H_{2}O+O_2$$ this implies that 2 moles of hydrogen peroxide produce one mole of oxygen gas.
The volume of oxygen gas released is 100 ml for 1 ml of $$H_2{O}_2$$ ​.
Since $$H_2{O}_2$$ ​ is 200 ml so total volume liberated is 20 litres.
1 mol of oxygen is 22.4 litres at NTP, so using the below formula we can get the number of moles present in 20 litres of peroxide
 $$numberofmoles={\displaystyle \frac{totalvolumeliberated}{volumeatNTP}}$$
So we have, the total volume liberated is 20 litres and volume at NTP is 22.4 litres. Putting these values in the above formula we get,
moles of oxygen $$={\displaystyle \frac{20}{22.4}}=0.89$$
Since 2 moles of $$H_2{O}_2$$ ​ produces 1 mol of oxygen so moles of hydrogen peroxide for two moles of oxygen will be double of 0.89 i.e., 1.78.
The molar mass of hydrogen peroxide is 34 grams per mole. Therefore, for 1.78 moles of hydrogen peroxide. The approximate mass will be 1.78 times of 34.
So, the approximate mass is 60.71 $$\simeq$$ 60.

Hence, the correct option is C.

Additional information:
Hydrogen peroxide is usually stored and kept in dark bottles as it can undergo self-decomposition and breaks down into water and oxygen. It acts as a powerful oxidising agent in spite of being non-flammable and causes instantaneous combustion on coming in contact with an organic material. We also use it as a bleaching agent for hair, paper, textiles, etc. and is known for its use in rocket fuel.

Note:
Hydrogen peroxide decomposes easily into two components – water and oxygen. But if it is made to decompose in an environment it will form different compounds i.e. hydrogen and oxygen whereas in vacuum only the water and oxygen molecules will be produced.
 $$H_2{O}_2\to H_2+{\displaystyle \frac{1}{2}}{O}_2$$