Processing: Preserving Materials is one of 9 topics in the Grade 9 Technology 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. Which metal preservation method coats steel with a protective layer of zinc?
Galvanising
Painting
Electroplating
Pickling
Answer: Galvanising — Galvanising coats steel with a protective layer of zinc, usually by dipping the steel into molten zinc.
Easy
2. What two conditions does metal need to be exposed to, in order to corrode (rust)?
Moisture and oxygen
Heat and light only
Salt and sugar
Pressure and vacuum
Answer: Moisture and oxygen — Metals, especially iron and steel, corrode when exposed to moisture and oxygen over time.
Medium
3. Name the metal preservation method that uses an electric current to deposit a thin layer of one metal onto another.
Answer: electroplating — Electroplating uses an electric current to deposit a thin layer of one metal onto the surface of another, by passing current through a chemical solution containing the plating metal.
