Name: Oxygen Worksheet 1. What is the symbol for Oxygen? __________ 3. What is the the mass number of Oxygen? __________ 2. What is the chemical formula of an Oxygen molecule? 4. Describe the laboratory TEST for Oxygen gas. __________ _______________________________________________________ _______________________________________________________ 5. Define the word catalyst. _______________________________________________________ _______________________________________________________ 6. Write a balanced chemical equation with state symbols, for the decomposition of hydrogen peroxide. _______________________________________________________ Exam question 7. The diagram below shows the laboratory preparation and collection of oxygen gas over water. a. Give the names of the items of the apparatus labelled A to D. [4 marks] ___________________________________________________ b. Name the solution X and the solid Y. [2 marks] ___________________________________________________ c. Why is it possible to collect oxygen over water? [1 mark] ___________________________________________________