What is the % carbon, by weight, in a 0.198g sample of C2H6??

Answer 1

C2H6 weighs:

(2 x 12.01) + (6 x 1.01) = 30.08g/mole

The wt % carbon is just the weight of the carbon divided by the total formula weight:

100% x [(2 x 12.01)/30.08g] = 79.85%

If you need grams of carbon in the 0.198g sample it would be:

0.7985 x 0.198g = 0.158g of carbon.

Answer 2

calculate the percentage of carbon present

12.01(2) + 1.008(8) = 24.02 + 8.064 = 32.084 g/mol

% carbon 32.084/24.02 = 75% of carbon and 25% hydrogen

75% X 0.198g = 0.1485 g