Properties of rocks · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Sorting rocks by their properties

Science · Earth's Systems · ages 7-8
Name ______________________   Date ____________

  1. Which word describes how easy a rock is to scratch or crumble?

    • Colour
    • Hardness
    • Grain size

  2. Which word describes how rough or smooth a rock feels?

    • Texture
    • Colour
    • Hardness

  3. Grain size tells you what colour a rock is.

    Circle one:   True   False

  4. Mia has a smooth white rock and a rough grey rock with big flecks of colour. Which sorting idea could she use?

    • Sort by texture: smooth vs rough
    • Sort by how much the rock weighs
    • Sort by how many rocks she has

  5. You scratch a rock with your fingernail and a mark appears. What does this tell you about the rock?

    • It is hard
    • It is soft
    • It is grey

  6. Two rocks can be the same colour but have different hardness.

    Circle one:   True   False

  7. Two rocks look the same grey colour, but one crumbles when scratched and one does not. Are they the same kind of rock?

    • Yes, because they are the same colour
    • Yes, because they are the same size
    • No, because they differ in hardness

  8. Leo sorts his rocks into 'grey' and 'brown' groups only. What should he check to also compare hardness?

    • Whether the rock scratches or crumbles
    • How many rocks are in each group
    • Whether the rock floats in water
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Answer key

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

Sorting rocks by their properties W1-mt_R6YoRXkRxS-s1

  1. Hardness · Hardness tells you how easily a rock scratches or crumbles.
  2. Texture · Texture is whether a rock feels rough or smooth when you touch it.
  3. False · Grain size tells you how big or small the bits inside a rock are, not its colour.
  4. Sort by texture: smooth vs rough · Texture separates a rock that feels smooth from one that feels rough.
  5. It is soft · A rock that marks or crumbles easily when scratched is soft.
  6. True · Colour is just one property. Rocks can match in colour but still differ in hardness or texture.
  7. No, because they differ in hardness · Colour alone does not decide if two rocks are alike. Hardness is a different property to compare.
  8. Whether the rock scratches or crumbles · Sorting by colour alone skips hardness. A scratch test checks hardness.
Worksheet · LightMySky