Question #b8d89

1 Answer
Dec 21, 2017

From the formula, there are 3 "C" atoms for every 8 "H" atoms. So...

Explanation:

5.60 * 10^24"H atoms" * "3 C atoms" / "8 H atoms" = 2.1* 10^24 "C atoms"

Now, to get to the mass of the sample, you must calculate the number of moles of "C"_3"H"_8 in the sample, and then use the molar mass of "C"_3"H"_8 to calculate the mass in grams:

5.60* 10^24 "H atoms" xx ("1 molecule C"_3"H"_8) / "8 H atoms" xx ("1 mole C"_3"H"_8) / (6.02xx10^23 "molecules") = "1.162 moles C"_3"H"_8

"Molar mass" = 3 xx "12 g/mol" + 8 xx "1 g/mol" = "44 g/mol"

So

"Total mass" = "1.162 moles C"_3"H"_8 xx "44 g/mol" = "51.1 g C"_3"H"_8