The apparatus that were used includes: test tubes, stopper, lighter, test tube holder, test tube rack, carbon paper, stirring rod, watch glass, litmus paper, dropper, dropping funnel, distilling flask (use in the preparation of acetylene gas), rubber tube and basin.
B. Procedure.
Before starting with all the experiment, our laboratory instructor prepared a set up for the extracting of acetylene gas needed for the entire tests. She put about 5 g of calcium carbide lumps into a dry distilling flask assemble the rest of the setup and she adds about 100 ml of water then allow a few drops to fall on the solid and wait a couple of minutes for the air to displaced from the apparatus. The gas evolved is the acetylene gas which is now ready to be used for the proceeding tests.
The first step is to investigate the given hydrocarbons samples (methane, acetylene, cyclohexane and toluene). We record our description (clarity, odor, and color) about the hydrocarbons that were given. For the following test, the first thing that we did is to label the test tubes with the name hydrocarbons to be tested. For the first test which is the combustion: ignition test we separated the liquid hydrocarbons and gas hydrocarbons since the two has the different way of testing its combustibility. For the liquid hydrocarbons, each must be placed in a porcelain crucible cover and bring the latter to the edge of the burner flame with the aid of crucible tong and record all the observations. For the gas hydrocarbons, the test tube filled with gas must be in upright position, remove the stopper, apply the flame with lighter and record all the observations. The second test that was made is the test for the reaction with bromine: effect of light. In doing this test, we placed one ml of the solution of bromine in carbon tetrachloride into each of two clean and dry test tubes. The first test tube must be wrapped with a carbon paper and the second test must remain as it is.