Chemistry mole question

Question

How many moles of carbon atoms are in 9.56 moles of stearic acid (formula CH3(CH2)16COOH)?

Answer 1

The first step is to find how many carbon atoms are in one molecule of stearic acid.

We find that this is an 18-carbon chain based on the fact that it has 1 CH₃, 16 CH₂'s and ends with a carboxylic acid (that's also 1 C)

We then use the understanding that 1 mole of a molecule can have multiple moles of individual atoms. (Remember, a mole is just a unit of counting, like a "dozen" - ex: a dozen molecules of stearic acid would be 12 molecules, but would have 12x18 atoms of carbon. We can use a mole in the same way *and remember that a mole is just a lot of something.. 6.022x10²³ of something*)

So now for some math: 9.56 moles of stearic acid (with 18 carbons each) would equal:

9.56 moles stearic acid x 18 moles of C = 172.08 moles of Carbon

1 1 mole stearic acid

Then we convert moles of atoms to number of atoms - just like 1 dozen bagels equals 12 bagels, 1 mole of bagels is just 6.022 x 10²³ bagels

172 moles C x 6.022 x 10^23 C atoms = 1.036 x 10²⁶ Carbon atoms

1 1 mole C