We need to determine the number of Cl2 molecules present in a chlorine gas sample with a mass of 39.2 grams.
Recall that based on Avogadro's number, there are 6.022 x 1023 entities for 1 mole of a substance.
This means that for 1 mole of Cl2 there are 6.022 x 1023 molecules
We need to solve for the # of moles for 39.2 g Cl2 to determine the number of Cl2 molecules
A sample of chlorine gas has a mass of 39.2 grams. How many Cl2 molecules are there in the sample?