Can someone please answer my question

Question

In lab you measure out 72.68 grams of C8H16O8 for an experiment. How many mol is this? Give your answer to 2 decimal spaces.

This is the only info I have for this question.

Answer 1

You can calculate the molecular weight of any molecule by adding the atomic weight of each atom in the molecule. We need:

Carbon: 8* 12.011 = 96.088 g/mol

Hydrogen: 16*1.008 = 16.128 g/mol

Oxygen: 8*15.999 = 127.992 g/mol

Add these components up and we get 240.21 g/mol of this compound. I would recommend just googling the molecular weight, though. It's much faster and just as accurate.

To find moles, we complete a stoichiometric ratio. Always start with what you HAVE and then work to what you WANT. We start with our 72.68 g. To cancel the g, we divide by g/mol. The grams unit will cancel and we are left with moles. It looks like this:

72.68 g / 240.21 g/mol = 0.303 moles C₈H₁₆O₈