Question

A substance is 35.7% carbon by mass. How much carbon could be recovered from 769 g of the substance? 1. 180 mol 2. 258 mol 3. 2290 mol 4. Not enough information is given. 5. 22.9 mol 6. 1.80 mol 7. 274 mol

Answer 1

Answer:

22.9 moles (Option 5)

Explanation:

A substance is 35.7% carbon by mass, means that in 100 g of substance, 35.7 g are C.

The rule of three will be:

100 g of substance ___ have __ 35.7 g of C

769 g of substance ___ have ___ ( 769 . 35.7) / 100 = 274.5 g of C

1 mol of C = 12 g/m

Mass / Molar mass = Moles

274.5 g / 12g/m = 22.9 moles