Molar Mass of Magnesium hydroxide
Mg(OH)2 — 58.319 g/mol, worked out element by element.
Molar mass of Magnesium hydroxide, Mg(OH)₂
58.319 g/mol
Molecular weight 58.319 · 5 atoms per formula unit
Also known as: mg(oh)2, milk of magnesia.
So sparingly soluble that it is safe to swallow as an antacid.
How 58.319 g/mol is worked out
| Element | Atoms | Atomic mass | Mass | % of total |
|---|---|---|---|---|
| Oxygen | 2 | 15.999 | 31.998 | 54.87% |
| Magnesium | 1 | 24.305 | 24.305 | 41.68% |
| Hydrogen | 2 | 1.008 | 2.016 | 3.46% |
| Total | 5 | 58.319 | 100% |
M = 2 × 15.999 + 1 × 24.305 + 2 × 1.008 = 58.319 g/mol
Grams to moles for Magnesium hydroxide
| Mass | Moles | Formula units |
|---|---|---|
| 1 g | 0.0171 mol | 1.033 × 10^22 |
| 10 g | 0.1715 mol | 1.033 × 10^23 |
| 25 g | 0.4287 mol | 2.582 × 10^23 |
| 50 g | 0.8574 mol | 5.163 × 10^23 |
| 100 g | 1.7147 mol | 1.033 × 10^24 |
| 250 g | 4.2868 mol | 2.582 × 10^24 |
| 58.319 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 hydroxide?
The molar mass of Magnesium hydroxide (Mg(OH)2) is 58.319 g/mol. That is the sum of the standard atomic weights of all 5 atoms in one formula unit: 2 × 15.999 + 1 × 24.305 + 2 × 1.008 = 58.319.
What is the molecular weight of Magnesium hydroxide?
58.319 — 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 58.32 and a molar mass of 58.32 g/mol are the same answer.
How many moles are in 100 g of Magnesium hydroxide?
100 ÷ 58.319 = 1.7147 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 hydroxide?
By mass, Magnesium hydroxide is 54.87% oxygen, 41.68% magnesium, 3.46% hydrogen. Each element's share is its total mass in the formula divided by 58.319.
How many atoms are in one formula unit of Magnesium hydroxide?
5: 2 oxygen, 1 magnesium, 2 hydrogen. One mole contains 6.02214076 × 10²³ formula units, so a mole of Magnesium hydroxide contains 5 × 6.022 × 10²³ atoms in total.