Quarter 2 Packet 3 WS #8
Making Hydrogen
Ming and Jeremiah sets up the apparatus. Jeremiah filled a test tube with water and inverted it in a water trough. The open end of the rubber tubing connected to the flask was put into the test tube as shown. Ming added 8.0 grams of granular zinc to a flask containing some concentrated hydrochloric acid
(HCl). Bubbles of gas began immediately. Ming Quickly put the stopper and tubing on the flask. Within minutes, the test tube was filled with gas.Placing his finger over the mouth of the test tube, Jeremiah removed the test tube from the water. When Ming placed a smoking match into the test tube, they heard the characteristic pop that indicates the presence of hydrogen.
1.What was the source of hydrogen in this experiment? Support your answers with observations.
2.What role does the zinc play in this reaction? Support your answer with observation.
3.Describe what the gas in the test tube would look like and smell like.
4.Which properties of hydrogen allowed it to push out, or displace, the water from the test tube?
5.The flask and the acid had a combined mass of 160.4 grams before the addition of 8.0 grams of zinc. Assuming that only hydrogen escaped durring the reaction, what mass of hydrogen was produced if the final mass of the flask and its contents were 163.2 Grams.
6.Explain what changes you could make to produce a greater mass of hydrogen.