A carbohydrate with the empirical formula CH2O has a molar mass of 150 g/mol. What is the molecular formula of this compound?
C is correct. C5H10O5.
The molecular formula is a multiple of the empirical formula, so the molar mass of CH2O times a whole number should equal 150 g/mol. The molar mass of CH2O is 12 g/mol (C) + 2 g/mol (2 H) + 16 g/mol (O) = 30 g/mol. This implies the molecular formula is 5-fold greater than the empirical formula, since 150 / 30 = 5. Therefore, we can multiply the subscripts of our empirical formula by 5 to obtain the molecular formula as such: (CH2O) x 5 = C5H10O5.