The percent composition of carbon in C6H12O6 is:

25% C

40% C

7% C

None of the above

To calculate percent composition, you first need to find the molar mass of C (carbon), H (hydrogen) and O (oxygen).

C is 12.01

H is 1.00

O is 16

Then multiply each by the number of atoms of each element in the formula (the number that comes after each element in the equation for example C6 means 6 carbon atoms.

C: 12.01 x 6 = 72.06

H: 1x12 = 12

O: 16x6 = 96

Then add them up.

72.06 + 12 + 96 = 180.06

Now find the percent composition of carbon.

72.06 / 180.06 x 100 = 40.01%

So the answer is C 40%.