Empirical formula:
1- A 1.35 g sample of a substance containing carbon, hydrogen, nitrogen and oxygen was burned to
produce 0.810 g H2O and 1.32 g CO2. In a separate reaction, all the nitrogen in 0.735 g of
the substance was converted to ammonia. This ga ve 0.284 g NH3. Determine the empirical
formula of the substance.
2- A 1.500 g sample of a substance composed of chromium and chlorine was dissolved in water
and allowed to react with AgNO3. This converted all the chlorine in the original sample
into AgCl, which was collected and found to weigh 4.072 g. What is the
empirical formula of the substance?
3- Dieldrin, an insecticide, contains C, H, Cl and O. Combustion of 29.72 mg of dieldrin gave 41.21
mg CO2 and 5.63 mg H2O. In a separate analysis 25.31 mg of dieldrin was converted into 57.13 mg
AgCl. What is the empirical formula of dieldrin?
(Atomic weights: C = 12.01, H = 1.008, O = 16.00, Cl = 35.45, Ag = 107.87).
4- A 1.365 g sample of a compound containing carbon, hydrogen, oxygen and nitrogen was burned to
produce 1.600 g CO2 and 0.819 g H2O. In a separate reaction, 3.754 g of the substance forms 0.852 g of
NH3. What is the empirical formula?
(Atomic weights: C = 16.00, H = 1.008, O = 16.00, N = 14.01).
5- A 1.35 g sample of a compound containing carbon, hydrogen, oxygen and nitrogen was burned to
produce 0.810 g H2O and 1.32 g CO2. In a separate reaction, 0.735 g of the substance was converted
into 0.284 g of NH3. What is the empirical formula of the compound?
(Atomic weights: C = 16.00, H = 1.008, O = 16.00, N = 14.01).
6- A 1.688 mg sample of a compound containing carbon, hydrogen, oxygen and nitrogen was burned to
produce 2.515 mg CO2 and 1.287 mg H2O. In a separate reaction, 3.938 mg of the substance forms
1.136 g of NH3. The approximate molecular weight is 126. What is the empirical formula?
(Atomic weights: C = 16.00, H = 1.008, O = 16.00, N = 14.01).
7- A 1.46 g sample of a compound containing only carbon, hydrogen and oxygen is burned in excess
oxygen to form 3.57 g of CO2 and 1.45 g of H2O. The approximate molecular weight is 144. What is
the molecular formula?
(Atomic weights: C = 12.01, O = 16.00, H = 1.008).