# How many moles are in 110.025 g of CO_2?

This is 2.5 moles of $C {O}_{2}$
Each mole of $C {O}_{2}$ has a mass of 44.01 g. This is known as the molar mass. So, to find the number of moles in any other mass, you divide that mass by the molar mass.
$\frac{110.025 g}{44.01 \left(\frac{g}{m o l}\right)} = 2.5 \text{moles}$