What is the molar mass of oxygen, O2? (Round to four significant figures only.) 32.00 g 16.00 g 15.99 g

32.00 g

Explanation:

The molar mass of one atom of oxygen is 16 g/mol.

So for the molecular oxygen or diatomic oxygen O₂:

2 * 16 g/mol

32 g/mol.

16 g of oxygen = one mole of oxygen = 6.022 * 10²³ atoms of oxygen

For O₂.

32 g of oxygen = one mole of oxygen = 6.022 * 10²³ molecules of oxygen

The number 6.022 * 10²³ is called Avogadro number.

It is the number of atoms, ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.