Module 5 · Practice
Practice questions
Three difficulty levels.
Section A — Easy
Complete: metal + acid → ____ + ____.
How would you test for hydrogen gas, and what would you observe?
Name the salt produced when zinc reacts with sulfuric acid.
List five metals in order of decreasing reactivity.
Match: ceramic / polymer / composite to: brittle, flexible, two-materials-combined.
Section B — Medium
A piece of magnesium is dropped into copper sulfate solution. State what you would see and write the word equation.
Predict whether each reaction happens. Give a reason.
Why is gold sometimes found as the pure metal in nature, while iron is always found as an ore?
Iron is extracted by heating iron oxide with carbon. Aluminium is extracted by electrolysis. Explain the difference.
Suggest a suitable material for each and give a reason:
Section C — Hard
Three metals X, Y and Z are added separately to dilute acid. X fizzes vigorously; Y fizzes slowly; Z does nothing. Use this to put them in order of reactivity, with reasoning.
A scientist heats copper(II) oxide with carbon and observes that copper appears. Write a word equation and state which substance has been reduced.
Explain why concrete (a composite of cement and aggregate) is widely used in construction, even though cement on its own is brittle.
Aluminium is extracted by electrolysis at high temperatures, which uses lots of energy. Suggest two reasons recycling aluminium is important.