Molar Mass of Magnesium oxide
MgO — 40.304 g/mol, worked out element by element.
Molar mass of Magnesium oxide, MgO
40.304 g/mol
Molecular weight 40.304 · 2 atoms per formula unit
Also known as: mgo, magnesia.
The white ash from burning magnesium ribbon, and a refractory that survives 2,800 °C.
How 40.304 g/mol is worked out
| Element | Atoms | Atomic mass | Mass | % of total |
|---|---|---|---|---|
| Magnesium | 1 | 24.305 | 24.305 | 60.30% |
| Oxygen | 1 | 15.999 | 15.999 | 39.70% |
| Total | 2 | 40.304 | 100% |
M = 1 × 24.305 + 1 × 15.999 = 40.304 g/mol
Grams to moles for Magnesium oxide
| Mass | Moles | Formula units |
|---|---|---|
| 1 g | 0.0248 mol | 1.494 × 10^22 |
| 10 g | 0.2481 mol | 1.494 × 10^23 |
| 25 g | 0.6203 mol | 3.735 × 10^23 |
| 50 g | 1.2406 mol | 7.471 × 10^23 |
| 100 g | 2.4811 mol | 1.494 × 10^24 |
| 250 g | 6.2029 mol | 3.735 × 10^24 |
| 40.304 g | 1 mol | 6.022 × 10^23 |
For any other amount, use the molar mass calculator, or the molarity calculator to make up a solution of a given concentration.
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Frequently Asked Questions
What is the molar mass of Magnesium oxide?
The molar mass of Magnesium oxide (MgO) is 40.304 g/mol. That is the sum of the standard atomic weights of all 2 atoms in one formula unit: 1 × 24.305 + 1 × 15.999 = 40.304.
What is the molecular weight of Magnesium oxide?
40.304 — 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 40.30 and a molar mass of 40.30 g/mol are the same answer.
How many moles are in 100 g of Magnesium oxide?
100 ÷ 40.304 = 2.4811 mol. To convert any mass to moles, divide by the molar mass; to go the other way, multiply.
What is the percent composition of Magnesium oxide?
By mass, Magnesium oxide is 60.30% magnesium, 39.70% oxygen. Each element's share is its total mass in the formula divided by 40.304.
How many atoms are in one formula unit of Magnesium oxide?
2: 1 magnesium, 1 oxygen. One mole contains 6.02214076 × 10²³ formula units, so a mole of Magnesium oxide contains 2 × 6.022 × 10²³ atoms in total.