Module 8 · Practice
Practice questions
Three difficulty levels.
Section A — Easy
Name the four layers of the Earth, from outside in.
Give the approximate percentages of nitrogen and oxygen in clean dry air.
State whether each rock is sedimentary, igneous or metamorphic:
Name two greenhouse gases.
Define the difference between weather and climate.
Section B — Medium
Explain why igneous rocks formed underground have larger crystals than those formed at the surface.
Describe how a sedimentary rock such as sandstone is formed, in three steps.
Sketch the four main carbon-cycle processes (photosynthesis, respiration, combustion, decomposition) and state whether each adds carbon to the atmosphere or removes it.
Why do volcanoes and earthquakes happen mostly near the edges of tectonic plates?
Aluminium is recycled rather than always extracted from new ore. Give two reasons why.
Section C — Hard
Explain how cutting down a forest and burning the wood affects the carbon cycle. Give two ways CO₂ in the atmosphere is increased.
Predict three consequences of average global temperatures rising by 2°C.
A scientist finds matching fossils of a freshwater reptile in rocks of the same age in both South America and Africa. Explain how this is evidence for plate tectonics.
Suggest why limestone, used in building, can be considered a "carbon sink" — and what happens to the carbon if the limestone is heated to make cement.