Calculate the number of molecules in a sample of carbon dioxide with a mass of 168.2 grams

2.30x10²⁴ molecules CO2

Explanation: Solution:

Convert mass of CO2 to moles

Convert moles of CO2 to molecules using Avogadro's number.

168.2 g CO2 x 1 mole CO2 / 44 g CO2 x 6.022 x10²³ molecules CO2 / 1 mole CO2

= 2.30 x10²⁴ molecules CO2