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Year 7 Science — Methods of separation

Name the everyday methods for pulling a mixture apart, and pick the right one for a given mixture.

Name: ________________________

Before you start

The stages of clearing a pan of tea, and where the leaves end up at each one.

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  1. 1. Sedimentation — the leaves settle at the bottom
  2. 2. Decantation — the tea is poured off the settled leaves
  3. 3. Filtration — the strainer catches the leaves still floating

Three stages, and each one leaves the tea a little cleaner. Decantation on its own still lets a few leaves through, which is why the strainer comes last.

  1. 1.Iron filings are mixed into a heap of sand. Which method gets the filings out?

    • a) Magnetic separation
    • b) Evaporation
    • c) Decantation
    • d) Winnowing

  2. 2.Sort each method by what it pulls apart.

    Groups: A solid from another solid · A solid from a liquid

    • Winnowing
    • Evaporation
    • Sieving
    • Magnetic separation
    • Sedimentation
    • Filtration
    • Handpicking

  3. 3.Sand has been stirred into water but has not dissolved. Which method separates it out?

    • a) Filtration
    • b) Threshing
    • c) Churning
    • d) Evaporation

  4. 4.Heavier insoluble bits are left to settle at the bottom of a liquid. What is that process called?

  5. 5.Put the three stages of clearing tea leaves out of a pan of tea back into order.

    • Leave the vessel undisturbed so the tea leaves settle at the bottom
    • Tilt the vessel and pour the tea off
    • Pour the tea through a strainer to catch the leaves still in it

  6. 6.Match each method of separation to what is done in it.

    • Winnowing
    • Sieving
    • Decantation
    • Magnetic separation
    • Threshing
    • using a magnet to draw the magnetic pieces out
    • beating stalks to free the grains
    • blowing air to carry the lighter husk away
    • tilting the vessel to pour the liquid off the settled solid
    • passing a mixture through a sieve to separate by particle size

  7. 7.In churning, where does the butter end up?

    • a) Dissolved into the buttermilk
    • b) Settled at the bottom, because it is heavier
    • c) Spread evenly through the whole mixture
    • d) Floating at the top, because it is lighter

  8. 8.Stalks are beaten so the grains come free of them. What is that process called?

Answer key — Year 7 Science — Methods of separation

  1. 1. a) Magnetic separation
  2. 2. Handpicking → A solid from another solid; Winnowing → A solid from another solid; Sieving → A solid from another solid; Magnetic separation → A solid from another solid; Filtration → A solid from a liquid; Sedimentation → A solid from a liquid; Evaporation → A solid from a liquid
  3. 3. a) Filtration
  4. 4. sedimentation
  5. 5. 1. Leave the vessel undisturbed so the tea leaves settle at the bottom 2. Tilt the vessel and pour the tea off 3. Pour the tea through a strainer to catch the leaves still in it
  6. 6. Winnowing → blowing air to carry the lighter husk away; Sieving → passing a mixture through a sieve to separate by particle size; Decantation → tilting the vessel to pour the liquid off the settled solid; Magnetic separation → using a magnet to draw the magnetic pieces out; Threshing → beating stalks to free the grains
  7. 7. d) Floating at the top, because it is lighter
  8. 8. threshing