# Question #b7094

Jan 21, 2015

You calculate how many atoms are in 1 mole of $\text{H"_2"O}$ by using Avogadro's number.

#### Explanation:

You'd go about calculating this by using Avogadro's number, which links the number of atoms or molecules of a substance with the number of moles of that substance you have.

According to this relationship, every mole has $6.022 \cdot {10}^{23}$ atoms (or molecules, depending on the substance).

Since water is a molecule, 1 mole of water will always have $6.022 \cdot {10}^{23}$ molecules of water.

LIkewise, 1 mole of ${\text{O}}_{2}$, for example, will have $6.022 \cdot {10}^{23}$ molecules of diatomic oxygen, 1 mole of sulfuric acid will have $6.022 \cdot {10}^{23}$ ${H}_{2} S {O}_{4}$ molecules, 1 mole of copper will have $6.022 \cdot {10}^{23}$ atoms of copper, and so on.