Answer:
2.258x 10 above 24 molecules
Explanation:
We use Avogadro's number of 6.022×1023 molecules per mole to calculate the number of molecules from the number of moles represented by 165 g of carbon dioxide.
The gram-molecular weight of carbon dioxide can be calculated from the atomic weights for carbon and oxygen (two of them in CO2) given in a Periodic Table of the Elements.
165 g CO244.01 g/mol×6.022×1023moleculesmol
=2.258×1024molecules