Extracting Metals: Reduction with Carbon and Choosing a Method · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Who pulls the metal free

Science · Matter & Materials · ages 14-15
Name ______________________   Date ____________
  1. Carbon reduces copper oxide to copper. What is oxidised?

    • The carbon
    • The copper
    • The oxygen
  2. Which metal can be extracted by heating its oxide with carbon?

    • Aluminium
    • Iron
    • Sodium
  3. Getting a metal from its oxide is always a reduction.

    Circle one:   True   False

  4. In the reaction of iron oxide with carbon, how do you spot what is reduced?

    • Find what burns brightest
    • Find what loses oxygen: the iron compound
    • Find what is heaviest
  5. Why must aluminium be extracted by electrolysis?

    • It sits above carbon in the reactivity series
    • It melts too easily
    • Carbon is too expensive
  6. Zinc sits below carbon and aluminium sits above. Which claim follows?

    • Both need electrolysis
    • Carbon extracts zinc but not aluminium
    • Carbon extracts aluminium but not zinc
  7. Mia says carbon frees aluminium because carbon burns very hot. What is wrong with her reason?

    • Heat never matters in chemistry
    • Position in the reactivity series decides, not how hot carbon burns
    • Aluminium is not a metal
  8. Iron tools were common while aluminium stayed precious. What best explains the price gap?

    • Iron ore sits nearer the surface everywhere
    • Aluminium tools break faster
    • Iron yields to cheap carbon reduction while aluminium needs costly electricity
LightMySky · lightmysky.comW1-mt_LRAEJa8OLr-s1

Answer key

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

Who pulls the metal free W1-mt_LRAEJa8OLr-s1

  1. The carbon · Carbon gains the oxygen as it burns, so carbon is oxidised.
  2. Iron · Iron sits below carbon, so carbon rips its oxygen away.
  3. True · The metal ion gains electrons and becomes free metal.
  4. Find what loses oxygen: the iron compound · Losing oxygen marks the reduced substance: the iron oxide.
  5. It sits above carbon in the reactivity series · Carbon cannot beat aluminium, so electricity does the pulling.
  6. Carbon extracts zinc but not aluminium · Position decides: below carbon falls to carbon, above needs electricity.
  7. Position in the reactivity series decides, not how hot carbon burns · Grip strength decides, and aluminium outgrips carbon however hot the fire.
  8. Iron yields to cheap carbon reduction while aluminium needs costly electricity · The power bill behind electrolysis made aluminium dear.
Worksheet · LightMySky