MDCAT Chemistry MCQ #3944

A compound contains 40% Carbon, 6.7% Hydrogen, and 53.3% Oxygen. If its molecular mass is 180, what is the number of carbon atoms per molecule?

MDCAT Chemistry MCQ #3944

  1. Question 1

    Q1. A compound contains 40% Carbon, 6.7% Hydrogen, and 53.3% Oxygen. If its molecular mass is 180, what is the number of carbon atoms per molecule?

    • A) 1
    • B) 3
    • C) 6
    • D) 12

    Answer: 6

    Explanation: The empirical formula CH2O (30g) fits six times into 180g. 3 is wrong, representing the empirical mass ratio instead.