17. What is the mass percent (%) for O in SO2? (b) 45.41 (a) 38.09 (c) 50.00 (d) 53.86 (e) 56.43 18. Which of the following is the empirical formula? (a) CSH18 (c) C4H1002 Hint: Empirical formula is the simplest integral ratio among each atom. (b) CH3COOH (d) NH4NO3 () -6 19. Chemical analysis shows the composition of a compound containing carbon, hydrogen, chlorine, and oxygen, to be 37.84% C, 2.12% H, 55.84% Cl, and 4.20% O. What is its empirical formula? () HCIO (b) C2HCIO4 (c) C12HsCl6O (d) C12H&Cl6O4 20. Chemical analysis shows the composition of a compound containing carbon and hydrogen, to be 80.00% carbon and 20% hydrogen and the molar mass is 30 g. What is its molecular formula? (a) CH (b) C2H4 (c) C2H6 (d) C6H12 (e) C10H22 21. What are the coefficients respectively when the equation PH3 + O2 P2Os +_H2O is balanced? - (a) 2, 2, 1, 3 (b) 2, 1, 3, 4 (c) 2, 3, 1, 2 (d) 2, 4, 1, 3 (e) 1, 1, 3, 3