gchem question from kaplan

[_veo_]

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Combustion of a 50 gram sample of an unknown
hydrocarbon yields 132 grams of CO2 and 126 grams
of H2O. Approximately how many grams of carbon
were contained in the original sample?
A. 14 g
B. 28 g
C. 36 g
D. 63 g
E. 66 g


please😕

 

[GRAD]

is it 36?

132/44
126/18

get 3 for CO2 then * 12= 36

 

[lifeisgood]

Assuming complete combustion...

(132 g CO2)/(44g/mol CO2) = 3 mol CO2

3 mol CO2 * (1 mol C/1mol CO2) * (12 g C/mol C) = 36 g C 😀

Hooray for dimensional analysis!

Damnit GRAD you type faster than me...

 

[_veo_]

thank you so much both
it is 36g!

*gives you a virtual cookie*