Question

How do the percent compositions for C3H6 and C4H7 compare?

A. They are the same
B. C4H8 has a higher percentage of carbon than C3H6.
C. C4H8 has a higher percentage of hydrogen than C3H6.
D. none of the above

Answer 1

A. They are the same

Further explanation

Given

C3H6 and C4H8

Required

The percent compositions

Solution

• C₃H₆(MW = 42 g/mol)

%C = 3.12/42 x 100% = 85.71%

%H = 6.1/42 x 1005 = 14.29%

C₄H₈(MW=56 g/mol)

%C = 4.12/56 x 100% = 85.71%

%H = 8.1/56 x 100%=14.29%

So they are the same, because mol ratio of C and H in both compounds is the same, 1: 2