The conditions needed for rusting, how rusting is prevented, why aluminium resists corrosion, and the environmental and health impact of heavy metals and metal mining.
6 narrated scenes. Press play, listen and read along — the points appear as they are explained. Use ‹ Prev / Next › or the scene bar to jump to any scene.
Rust costs the Caribbean billions a year in damaged cars, roofs and bridges, and the cause is nothing more than air and water.
Narration uses your device’s built-in voice. No sound? Switch to “Captions only” — the captions advance on their own.
Copy these into your notebook in your own words — that is how they stick.
Needs oxygen AND water; hydrated iron(III) oxide.
Salt, acid, heat.
Paint, oil, plastic, tin plating.
Zinc coat: barrier + sacrificial.
More reactive metal blocks.
Oxide layer protects the metal.
Toxic; bioaccumulate (Pb, Hg, Cd).
Deforestation, red mud, pollution; recycling reduces impact.
3 quick games on this lesson. Earn XP and badges as you play — your best score for each game is saved. Games are for practice and do not change your exam readiness. More games in the Chemistry Arcade.
8 items modelled on real CSEC Paper 1 questions. Choose one answer for each, then check. Aim for 80% or better. Work each item on paper first.
Write full answers, then reveal the mark scheme and tick the points you earned (13 marks in total). Show all your working — method marks count. Your answers are saved on this device.
Question 1 [13 marks]
A student sets up four test tubes, each with an iron nail: (1) air and water, (2) boiled water covered with oil, (3) dry air with anhydrous calcium chloride, (4) salt water.
(a) (a) State which test tubes the nails rust in and explain. [3]
(b) (b) State the purpose of the oil in tube 2 and of calcium chloride in tube 3. [2]
(c) (c) Name the compound that forms when iron rusts. [1]
(d) (d) Describe how galvanising prevents rusting. [3]
(e) (e) Explain why aluminium does not corrode in air even though it is very reactive. [2]
(f) (f) State one harmful effect of a heavy metal and one way of reducing the impact of mining. [2]
Find these in your own past-paper booklets for extra timed practice. Items above are written in the style of these papers; any adapted from a specific question say so.