For which compound does 0.256 mole weigh 12.8 g?

a) (c_2 h_4 o)
b) (co_2)
c) (ch_3 cl)
d) (c_2 h_6)
e) none of these

To answer this problem, we divide the mass in grams of the compound by the number of moles of the compound. In this case, 12.8 grams divided by 0.256 is equal to 50 g/mol. We just have to find which among the choices has a molar mass of 50 g/mol. The answer to this problem is C. CH3Cl

B. Adenine and thymine.
It is always A pairing with T and G with C.