Simply start new topic. There is such a button somewhere on your screen when you are logged and browse chemicalforums
No reference, unless you dare to quote my previous post. However, if you start with formula for hemoglobine and calculate its molar mass, and then you check how much carbon does one mole of hemoglobine contain, you will get to the same number I have posted. It holds only statistically - ie only assuming that other proteins have similar ratio of aminoacids used, which is most likely close enough to reality. I have used similar approach to find out number for fat, starting with the formula C
55H
98O
6.
In many places you will be not allowed to use wikipedia as reference. I wonder if taking an example formula for huge molecule will be treated this way.