Question

"How many moles of ethane (C2H6) contain 8.46 x 10^24 formula units?"

a) 1.41 moles

b) 2.82 moles

c) 4.65 moles

d) 8.46 moles

Answer 1

To determine the number of moles, divide the number of formula units by Avogadro's number. The correct answer is (a) 1.41 moles.

Step-by-step explanation:

To determine the number of moles of ethane (C2H6) that contain 8.46 x 10^24 formula units, we need to use Avogadro's number and the molar mass of ethane. Avogadro's number is approximately 6.022 x 10^23 formula units/mol. The molar mass of ethane is calculated by adding up the atomic masses of carbon (C) and hydrogen (H) in the formula C2H6. Carbon has an atomic mass of approximately 12.01 amu, while hydrogen has an atomic mass of approximately 1.008 amu. So the molar mass of ethane is (12.01 amu x 2) + (1.008 amu x 6) = 30.07 amu.

To find the number of moles, we can use the formula:

moles = number of formula units / Avogadro's number

moles = (8.46 x 10^24) / (6.022 x 10^23)

moles ≈ 14.03