Reactions of Metals, Non-metals, Acids and Bases is one of 9 topics in the Grade 9 Natural Sciences CAPS syllabus, covered across 3 lessons on Study Vault. Below are real practice questions from this topic with full worked answers.
Sample practice questions
Easy
1. What product is formed when a metal reacts with oxygen?
A metal oxide
A non-metal oxide
A salt
An acid
Answer: A metal oxide — When a metal reacts with oxygen, a metal oxide is formed as a product: metal + oxygen -> metal oxide.
Easy
2. What is rusting?
A slow chemical reaction of iron with oxygen and moisture to form a compound containing iron oxide
A fast reaction of iron with only oxygen, no moisture involved
A reaction that only happens to non-metals
A physical, non-chemical change to iron
Answer: A slow chemical reaction of iron with oxygen and moisture to form a compound containing iron oxide — Rusting is a slow chemical reaction of iron metal with oxygen and moisture (water) to form a complex compound, part of which is iron oxide.
Medium
3. Name ONE way, mentioned in this lesson, that rusting can be prevented.
Answer: painting — Rusting can be prevented by painting iron/steel to keep away moisture and oxygen, or by coating it with a non-rusting metal like chromium or zinc.
