Consider a 15.00-g sample of CO2 . How many moles of CO2 are there in this sample?

To find the number of moles in a sample, you need to know the molar mass of the substance. The molar mass of CO2 (Carbon Dioxide) is approximately 44.01 g/mol. This is calculated by adding the molar mass of Carbon (C ~ 12.01 g/mol) and Oxygen (O ~ 16.00 g/mol) multiplied by 2 (since there are two oxygen atoms in CO2).

The formula to calculate the number of moles (n) is:

n = mass (g) / molar mass (g/mol)

So, for a 15.00-g sample of CO2:

n = 15.00 g / 44.01 g/mol

This gives approximately 0.341 moles of CO2.