Question

10 ml of H2O2 sample gives 250 ml O2 at STP. The molarity of this sample is

Answer 1

Answer:

correct

answer is 0.00865..

Answer 2

Answer:

The molarity of this sample would be equal to 2.23M.

Explanation:

The decomposition reaction:

$2H_{2}O_{2}$  → $2H_{2}O +O_{2}$

From the above reaction, we can conclude that two mole of H₂O₂ gives one mole of O₂.

$1 mmol$ of gas has volume$=22.4ml$

Number of moles of 112ml of $O_{2}$ $=\frac{250}{22.4}=11.16mmol$

Number of moles $H_{2}O_{2}$ $=2*11.16=22.32mmol$

Molarity = (number of moles)/(volume of solution)

Molarity $=\frac{22.32mmol}{10}=2.23M$