Final answer:
To determine the number of molecules in each sample, calculate the number of moles using the sample's mass and the substance's molar mass, then multiply by Avogadro's number (6.02 x 10^23 molecules/mol).
Step-by-step explanation:
The student is asking about the number of molecules or formula units present in different samples of substances. To find the number of molecules or formula units, we first have to determine the number of moles in each sample using the molar mass of the substance and then use Avogadro's number (6.02 x 1023 molecules or formula units per mole) to find the total number of molecules.
- For CCl4, NaHCO3, C4H10, and Na3PO4, we would calculate their respective molar masses and then divide the given mass of the sample by the molar mass to find the number of moles. Then, multiply the number of moles by Avogadro's number to get the number of molecules or formula units.
- For example, if we want to find the number of molecules in a 94.26 g sample of CCl4, we would calculate the molar mass of CCl4, divide 94.26 g by that molar mass to get moles, and finally multiply by Avogadro's number.