Molar Mass of Aluminium hydroxide
Al(OH)3 — 78.003 g/mol, worked out element by element.
Molar mass of Aluminium hydroxide, Al(OH)₃
78.003 g/mol
Molecular weight 78.003 · 7 atoms per formula unit
Also known as: al(oh)3, aluminum hydroxide.
Amphoteric: it reacts with acids and with strong bases, which is unusual enough to be examinable.
How 78.003 g/mol is worked out
| Element | Atoms | Atomic mass | Mass | % of total |
|---|---|---|---|---|
| Oxygen | 3 | 15.999 | 47.997 | 61.53% |
| Aluminum | 1 | 26.982 | 26.982 | 34.59% |
| Hydrogen | 3 | 1.008 | 3.024 | 3.88% |
| Total | 7 | 78.003 | 100% |
M = 3 × 15.999 + 1 × 26.982 + 3 × 1.008 = 78.003 g/mol
Grams to moles for Aluminium hydroxide
| Mass | Moles | Formula units |
|---|---|---|
| 1 g | 0.0128 mol | 7.720 × 10^21 |
| 10 g | 0.1282 mol | 7.720 × 10^22 |
| 25 g | 0.3205 mol | 1.930 × 10^23 |
| 50 g | 0.6410 mol | 3.860 × 10^23 |
| 100 g | 1.2820 mol | 7.720 × 10^23 |
| 250 g | 3.2050 mol | 1.930 × 10^24 |
| 78.003 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.
Related compounds
Related Calculators
Frequently Asked Questions
What is the molar mass of Aluminium hydroxide?
The molar mass of Aluminium hydroxide (Al(OH)3) is 78.003 g/mol. That is the sum of the standard atomic weights of all 7 atoms in one formula unit: 3 × 15.999 + 1 × 26.982 + 3 × 1.008 = 78.003.
What is the molecular weight of Aluminium hydroxide?
78.003 — 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 78.00 and a molar mass of 78.00 g/mol are the same answer.
How many moles are in 100 g of Aluminium hydroxide?
100 ÷ 78.003 = 1.2820 mol. To convert any mass to moles, divide by the molar mass; to go the other way, multiply.
What is the percent composition of Aluminium hydroxide?
By mass, Aluminium hydroxide is 61.53% oxygen, 34.59% aluminum, 3.88% hydrogen. Each element's share is its total mass in the formula divided by 78.003.
How many atoms are in one formula unit of Aluminium hydroxide?
7: 3 oxygen, 1 aluminum, 3 hydrogen. One mole contains 6.02214076 × 10²³ formula units, so a mole of Aluminium hydroxide contains 7 × 6.022 × 10²³ atoms in total.