Question

3. In the lab today you prepared oxygen gas by decomposing hydrogen peroxide. There are many other chemical reactions that generate gases as one of their products. Lets consider the reaction between zinc metal and hydrochloric acid as such an example. a) (2 pts) What are the products of the chemical reaction that occurs when zinc metal is added to an aqueous solution of Hydrochloric acid? b) (3 pts) Write the chemical equation that represents this reaction? c) (4 pts) Write a procedure that explains how you would collect the gas produced from this reaction in the laboratory. 4. Imagine that you are given two metal oxides to study in the lab. You heat each oxide in a small test tube and then insert a glowing splint into each. You observe that the splint in tube 1 immediately ignites and burns with a steady flame before it dies, but the splint in tube 2 does not. a) (2 pts) What happened to the metal oxide in tube 1 when it was heated? b) (4 pts) Do both metal oxides decompose when heated? Provide evidence to support your answer c) (2 pts) What can you conclude about the stability of the 2 oxides based on these observations?

Answer 1

Question 3.

a) The products are aqueous zinc chloride and hydrogen gas, i.e. ZnCl₂(aq) and H₂(g).

b) Zn(s) + 2HCl(aq) ----> ZnCl₂(aq) + H₂(g)

c) The H₂(g) (hydrogen gas) can be collected if the reaction is performed in a reactor with a closed valve, and the reactor's nob can be opened at the time of high pressure and all the gas can be collected into a cylinder through a mini-gas pipe connection.