TUTORIAL - MOLE AND ATOMIC CONCEPT

Tutorial 1

Mole and Atomic Concept

1.		Hydrocarbons are organic compounds composed entirely of hydrogen and carbon. A 0.1647 g sample of a pure hydrocarbon was burned in a C-H combustion train to produce 0.4931 g of CO2 and 0.269 g of H2O. Determine the masses of C and H in the sample and the percentage of these elements in this hydrocarbon.
2.		Compounds containing sulphur and oxygen are serious air pollutants; they represent the major cause of acid rain. Analysis of a sample of a pure compound reveals that it contains 50.1 % sulphur and 49.9 % oxygen by mass. Determine the simplest formula of the compound?
3.		A 20.882 g sample of an ionic compound is found to contain 6.072 g of Na, 8.474 g of S and 6.33 g of O. determine the simplest formula of the compound?
4.		A 0.1014 g sample of purified glucose was burned in a C-H combustion train to produce 0.1486 g of CO2 and 0.0609 g of H2O. An elemental analysis showed that the glucose contains only carbon, hydrogen and oxygen. i)       Determine the masses of C, H and O in the sample. ii)     Other experiments show that its molecular weight is approximately 180 amu. Determine the simplest formula of glucose.
5.		Calcium carbonate (CaCO3) are called calcite, is the principal mineral found in limestone, marble, chalks, pearls, and the shells of marine animals such as clams. i)       Calculate the molar mass of calcium carbonate. ii)     A certain sample of calcium carbonate contains 4.86 moles. What is the mass in g of these samples? iii)    What is the mass of the CO32- ions present?