Molar MassMolar mass of titanium dioxide (TiO2)
The molar mass of titanium dioxide, TiO2, is 79.86 g/mol. One mole of it, which is 6.022 × 1023 formula units, has a mass of 79.86 grams.
79.86 g/mol
47.867 + 2 × 15.999 = 79.865 · 3 atoms in the formula · also called titania
About titanium dioxide
Titanium dioxide is the brilliant white pigment in paint, paper, toothpaste and sunscreen.
Other names: titania.
The working
The formula TiO2 has 1 titanium atom and 2 oxygen atoms, 3 atoms in all. Multiply each count by the atomic weight of the element and add:
| Element | Atoms | Atomic weight | Total | Share by mass |
|---|---|---|---|---|
| Titanium (Ti) | 1 | 47.867 | 47.867 | 59.93% |
| Oxygen (O) | 2 | 15.999 | 31.998 | 40.07% |
47.867 + 2 × 15.999 = 79.865 g/mol
With the rounded atomic masses used in many school books (Ti = 48, O = 16) the answer is 80 g/mol. The difference from 79.86 is too small to matter in most school sums.
Percentage composition
By mass, TiO2 is 59.93% titanium and 40.07% oxygen. The largest share comes from titanium. In a 100 g sample there are 59.9 g of titanium and 40.1 g of oxygen.
Notice that oxygen has more atoms in the formula (2) than titanium (1), yet gives a smaller share of the mass. Percentage by mass depends on how heavy each atom is, not only on how many there are.
Worked examples
Grams to moles. How many moles are in 20 g of TiO2? Divide the mass by the molar mass: 20 ÷ 79.86 = 0.2504 mol.
Moles to grams. What is the mass of 0.5 mol of TiO2? Multiply: 0.5 × 79.86 = 39.93 g.
Counting particles. 20 g contains 0.2504 mol × 6.022 × 1023 = 1.508 × 1023 formula units.
Quick conversion tables
| Amount | Mass |
|---|---|
| 0.1 mol | 7.986 g |
| 0.5 mol | 39.93 g |
| 1 mol | 79.86 g |
| 2 mol | 159.7 g |
| 5 mol | 399.3 g |
| Mass | Moles |
|---|---|
| 1 g | 0.01252 mol |
| 10 g | 0.1252 mol |
| 100 g | 1.252 mol |
| 1 kg | 12.52 mol |
For other amounts use the grams and moles converter.
Questions people ask
What is the molar mass of TiO2?
The molar mass of titanium dioxide (TiO2) is 79.86 g/mol, or 79.865 g/mol before rounding, using IUPAC abridged atomic weights.
How many moles are in 100 g of TiO2?
100 ÷ 79.86 = 1.252 mol.
What is the mass of one formula unit of TiO2?
Divide the molar mass by the Avogadro constant: 79.86 ÷ 6.022 × 1023 = 1.326 × 10-22 g.
What is the percentage of titanium in TiO2?
Titanium makes up 59.93% of the mass of TiO2: 1 × 47.867 ÷ 79.865 × 100.
Which values? This site uses the abridged standard atomic weights published by IUPAC (CIAAW), read on 12 November 2026. Your textbook or question paper may round them differently, for example H = 1 and O = 16, so its answer can differ slightly. In an exam, use the values the paper gives.