Question

A sample of C₃H₈ contains 3.04 × 10²4 molecules. What is the mass of the sample?

a) Mass = 48.06 g
b) Mass = 32.04 g
c) Mass = 64.08 g
d) Mass = 96.12 g

Answer 1

To find the mass of the C₃H₈ sample, calculate the number of moles using Avogadro's number and then multiply by the molar mass of C₃H₈, resulting in a mass that is not listed in the answer choices, indicating a possible miscalculation in the given choices.

Step-by-step explanation:

To determine the mass of a sample of C₃H₈ containing 3.04 × 10²⁴ molecules, we first need to use Avogadro's number, which is 6.02 × 10²⁳ molecules per mole, to find the number of moles in the sample. We then multiply the number of moles by the molar mass of C₃H₈ to find the mass in grams.

First, calculate the number of moles:
Number of moles = (3.04 × 10²⁴ molecules) / (6.02 × 10²⁳ molecules/mol) = 5.05 × 10° moles

Next, calculate the molar mass of C₃H₈:
Molar mass of C₃H₈ = (3 × 12.01 g/mol) + (8 × 1.008 g/mol) = 44.094 g/mol

Finally, calculate the mass of the sample:
Mass = Number of moles × Molar mass of C₃H₈ = 5.05 moles × 44.094 g/mol = 222.6747 g