Term 1 review: Units 1 to 4
Answers are for parents and teachers.
1
Draw a heating curve for an invented substance with melting point 30 °C and boiling point 90 °C. Label the states.
Rise to 30 °C (solid); flat at 30 °C (melting); rise to 90 °C (liquid); flat at 90 °C (boiling); rise (gas).
2
Balance: K + O₂ → K₂O and H₂O₂ → H₂O + O₂, and count the atoms.
4K + O₂ → 2K₂O (4 K, 2 O); 2H₂O₂ → 2H₂O + O₂ (4 H, 4 O).
3
Explain how photosynthesis and cellular respiration are linked.
The products of one (glucose and oxygen, or CO₂ and water) are the inputs of the other; one stores energy, the other releases it.
4
Match each to a boundary: the Red Sea, the Himalayas, the San Andreas fault.
Divergent, convergent, transform.
5
Find the mistake: “A mineral can be made from living things, like coal.”
Minerals are non-living (inorganic); coal comes from plants and is a fossil fuel.