Calculate the molecules of oxygen gas in 20.6 moles. Round to 3 significant figures.

1.24 × 10²⁵ molecules of oxygen gas

Explanation:

Step 1: Given data

Moles of oxygen gas: 20.6 moles

Step 2: Calculate the number of molecules present in 20.6 moles of oxygen gas

In order to convert moles to molecules, we need a conversion factor. In this case, we will use Avogadro's number: there are 6.02 × 10²³ molecules in 1 mole of molecules.

20.6 mol × 6.02 × 10²³ molecules/1 mol = 1.24 × 10²⁵ molecules