# The label on a laundry stain remover indicates that it contains 50 g/L hydrogen peroxide (H2O2). What is the molarity of the hydrogen peroxide?

justaguide | College Teacher | (Level 2) Distinguished Educator

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The label on the laundry stain remover indicates that it contains 50 g/L hydrogen peroxide (H2O2). The molarity of the hydrogen peroxide solution has to be determined.

To find the molarity of hydrogen peroxide the molar mass of hydrogen peroxide has to be determined first. This can be done by adding the mass of 2 hydrogen atoms and 2 oxygen atoms, giving 2*2 + 16*2 = 38 g/mole.

As the solution has 50 g/L of hydrogen peroxide, the number of moles of hydrogen peroxide in one liter of the solution is required. This is equal to 50/38 = 1.315.

This gives the concentration of hydrogen peroxide in moles/liter as 1.315 or the molarity is 1.315 M

lochana2500 | Student, Undergraduate | (Level 1) Valedictorian

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H₂O₂ 34g → 1mol

H₂O₂50g → 1*50/34 mol

H₂O₂50g → 50/34 mol

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H₂O₂50gL⁻¹

1L → 50g

1L → 50/34 mol

1dm⁻³ → 50/34 mol

Hence Molarity = 50/34 M ~ 1.47M