Chemical Reactions — Introduction

Grade 8 Science — Chemical Reactions — Introduction: 25 practice questions with instant scoring and explanations.

1. A combination reaction is one where:
2. An example of a decomposition reaction is:
3. A displacement reaction occurs when:
4. In a double displacement reaction:
5. Which of the following is a balanced equation?
6. The purpose of balancing a chemical equation is to:
7. A word equation shows:
8. The chemical equation for the combustion of methane (CH4) in oxygen is:
9. When sodium (Na) reacts with water, the products are:
10. An exothermic reaction is one that:
11. An endothermic reaction is one that:
12. Combustion reactions are always:
13. A reversible reaction is one that:
14. The law of conservation of mass states that:
15. A catalyst is a substance that:
16. The reaction between zinc and dilute sulfuric acid produces:
17. When calcium carbonate is heated, it decomposes to form:
18. The reactivity series of metals helps predict:
19. In the reactivity series, iron is more reactive than:
20. Rusting is an example of:
21. The balanced equation for the reaction between hydrogen and oxygen is:
22. When a metal reacts with a non-metal, the product is usually:
23. Thermal decomposition occurs when:
24. The products of burning carbon in limited oxygen are:
25. A reaction is said to be complete when: