Question

Household hydrogen peroxide is an aqueous solution containing 3.0% hydrogen peroxide by mass. What is the molarity of this solution? (Assume a density of 1.01 g/mL.)

Answer 1

Answer:

Molarity = 8.89 mol/L

Explanation:

Given data:

Mass of hydrogen peroxide = 3%

Density = 1.01 g/mol

Molarity = ?

Solution:

3% hydrogen peroxide means 3 g of H₂O₂ are present in 100 g of solution.

Now we will calculate the moles of H₂O₂.

Number of moles = mass / molar mass

Number of moles = 3g/ 34 g/mol

Number of moles = 0.88 mol

Now we calculate the volume of solution.

d = m/v

v = m/ d

v= 100 g/ 1.01 g/ mL

v = 99 mL

In Litter

v = 99 / 1000 = 0.099 L

Molarity:

Molarity = number of moles / volume in L

Molarity = 0.88 mol/ 0.099 L

Molarity = 8.89 mol/L