Finite Resources & Recycling · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Finite Resources & Recycling

Science · Matter & Materials · ages 12-14
Name ______________________   Date ____________

  1. Because finite resources took millions of years to form, humans can quickly make more whenever supplies run low.

    Circle one:   True   False

  2. Which of these is an example of a finite resource?

    • Coal
    • Sunlight
    • Wind

  3. What is one environmental cost of mining for metals?

    • It cools down the atmosphere
    • It can pollute rivers with waste
    • It creates new fossil fuels

  4. The chart shows new aluminium uses 100 units of energy and recycled aluminium uses 5 units. How many fewer units does recycled aluminium use?

    Newaluminium100Recycledaluminium5

    Answer: ______________

  5. Why does recycling aluminium use much less energy than making new aluminium from ore?

    • Recycled metal weighs less than new metal
    • Old cans are made of a lighter metal than new cans
    • It skips the electrolysis step needed to split aluminium from its ore

  6. A power plant burns more coal and oil to make electricity. What environmental effect does this most directly cause?

    • More greenhouse gases entering the atmosphere
    • More recycled aluminium being produced
    • Less demand for mining

  7. Priya says trees are a finite resource in the same way coal is, since only a limited number are growing right now. Why is this not quite right?

    • Coal and ore also regrow within a few years, just like trees
    • Trees are actually infinite and can never run out
    • Trees can regrow over years, while coal and ore take millions of years to reform

  8. A town says recycling costs too much in trucks and workers, so it should stop collecting metal for recycling. What is the strongest argument against this?

    • Recycling makes new metal appear instantly for free
    • Recycling still saves large amounts of energy and keeps finite ore in the ground
    • Mining never has any costs to weigh against
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Answer key

For grown-ups. Fold this page away before handing over the rest.

Finite Resources & Recycling W1-mt_0e5rZxbAeR-s1

  1. False · There is no quick way to remake coal, oil, or metal ore. Once a source is used up, it stays used up for a very long time.
  2. Coal · Coal took millions of years to form underground. Sunlight and wind keep arriving fresh every day.
  3. It can pollute rivers with waste · Waste chemicals from mining can run off into nearby water, harming rivers and soil.
  4. 95 · 100 minus 5 leaves 95 fewer units of energy for recycled aluminium.
  5. It skips the electrolysis step needed to split aluminium from its ore · Aluminium is reactive, so pulling it from ore takes a lot of electricity. Melting down existing metal skips that step.
  6. More greenhouse gases entering the atmosphere · Burning fossil fuels releases carbon dioxide and other gases into the atmosphere.
  7. Trees can regrow over years, while coal and ore take millions of years to reform · Resources like trees can be replanted and regrown in a human lifetime, but coal, oil, and metal ores take far too long to reform, so we treat those as finite.
  8. Recycling still saves large amounts of energy and keeps finite ore in the ground · The trade-off is real: recycling costs money to run, but the energy and resource savings usually outweigh that cost.
Worksheet · LightMySky