The molecular formula mass of this compound is 120 amu. What are the subscripts in the actual molecular formula? Enter the subscripts for C, H, and O

The simplest formula i. e, empirical formula of the organic molecule having molar mass 120 can be assumed to be CH₂O, because if we consider the simplest formula as CHO then empirical formula mass becomes (12+1+16) = 29 which can never be possible if molecular mass of the compound is 120 as molecular formula can not be fractional. If empirical formula is CH₂O, then empirical formula mass becomes (12+2+16) = 30 by which 120 is divisible. So, the molecular formula is considered as - (CH₂O) ₓ, where x = positive integer.

Mass of (CH₂O) ₓ=120, which indicates (12+2+16) X x = 120

So, 30x = 120, x=4. Hence the molecular formula is C₄H₈O₄.

Subscript for C=4, H=8, O=4.