Solution of the problem 486 of the collection of genera

Solution of the problem 486 of the collection of genera

486. In 60 g of benzene, 2.09 g of a certain substance was dissolved, the elemental composition [in% (by mass)] of which: C = 50.69, H2 = 4.23 and O2 = 45.08. The solution crystallizes at 4.25 ° C. Set the molecular formula of the substance. Pure benzene crystallizes at 5.5 ° C