Molar Mass of Hydrogen peroxide

H2O2 — 34.014 g/mol, worked out element by element.

Molar mass of Hydrogen peroxide, H₂O₂

34.014 g/mol

Molecular weight 34.014 · 4 atoms per formula unit

Also known as: h2o2, peroxide.

One extra oxygen against water, and a completely different oxidising character.

How 34.014 g/mol is worked out

Mass contribution of each element
ElementAtomsAtomic massMass% of total
Oxygen215.99931.99894.07%
Hydrogen21.0082.0165.93%
Total434.014100%

M = 2 × 15.999 + 2 × 1.008 = 34.014 g/mol

Grams to moles for Hydrogen peroxide

Mass to moles conversions
MassMolesFormula units
1 g0.0294 mol1.770 × 10^22
10 g0.2940 mol1.770 × 10^23
25 g0.7350 mol4.426 × 10^23
50 g1.4700 mol8.852 × 10^23
100 g2.9400 mol1.770 × 10^24
250 g7.3499 mol4.426 × 10^24
34.014 g1 mol6.022 × 10^23

For any other amount, use the molar mass calculator, or the molarity calculator to make up a solution of a given concentration.

Related compounds

Can't find the exact calculator you need?

Describe it in one sentence — get a working, math-verified calculator in seconds. Free, no signup.

Build your own calculator

Related Calculators

Frequently Asked Questions

What is the molar mass of Hydrogen peroxide?

The molar mass of Hydrogen peroxide (H2O2) is 34.014 g/mol. That is the sum of the standard atomic weights of all 4 atoms in one formula unit: 2 × 15.999 + 2 × 1.008 = 34.014.

What is the molecular weight of Hydrogen peroxide?

34.014 — the same number as the molar mass, but as a dimensionless ratio rather than in g/mol. The two terms describe the same arithmetic, so a molecular weight of 34.01 and a molar mass of 34.01 g/mol are the same answer.

How many moles are in 100 g of Hydrogen peroxide?

100 ÷ 34.014 = 2.9400 mol. To convert any mass to moles, divide by the molar mass; to go the other way, multiply.

What is the percent composition of Hydrogen peroxide?

By mass, Hydrogen peroxide is 94.07% oxygen, 5.93% hydrogen. Each element's share is its total mass in the formula divided by 34.014.

How many atoms are in one formula unit of Hydrogen peroxide?

4: 2 oxygen, 2 hydrogen. One mole contains 6.02214076 × 10²³ formula units, so a mole of Hydrogen peroxide contains 4 × 6.022 × 10²³ atoms in total.