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

Dissolving and solutions

Science · Matter & Materials · ages 9-10
Name ______________________   Date ____________

  1. When a solid dissolves in a liquid, the solid is still there, even though you cannot see it.

    Circle one:   True   False

  2. Aisha stirs instant drink powder into a glass of water. Soon the powder is gone from sight and the drink is one smooth color. What happened to the powder?

    • It sank to the bottom and stayed there
    • It turned into water vapor
    • It dissolved into the water

  3. Miko stirs soil into water. The water turns cloudy and dark bits settle at the bottom. Did the soil dissolve?

    • Yes, cloudy water means the soil dissolved
    • No, the soil bits are still visible
    • Yes, but only the smallest bits dissolved

  4. Ben stirs ground pepper into water. Dark specks float and sink all through the glass. What happened?

    • The pepper dissolved into the water
    • The pepper evaporated into the air
    • The pepper did not dissolve

  5. Ella wants to get the drink powder back out of her finished drink. What should she do?

    • Pour the drink through a filter
    • Stir in more drink powder
    • Warm it so the water evaporates

  6. How can you get the salt back from salty water?

    • Filter the water through paper
    • Let the water evaporate away
    • Stir the water faster

  7. Priya mixes sand and water. She can still see sand grains sitting at the bottom. What did Priya make?

    • A solution
    • A mixture
    • A gas

  8. Sam has four mixes on his table: salt water, sugar water, drink-powder water, and sand water. How many of them are solutions?

    Answer: ______________

  9. Femi says, 'I poured my salt solution through a filter, and the paper caught all the salt.' What is wrong with Femi's idea?

    • Dissolved salt slips through with the water
    • Nothing, filter paper always catches salt
    • Salt cannot dissolve in water, so there was nothing to filter

  10. Zoe pours muddy water through a filter. The mud stays on the paper and clear water drips through. Why did the filter catch the mud?

    • Because the mud dissolved in the water
    • Because the water turned the mud into vapor
    • Because the mud never dissolved
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Answer key

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

Dissolving and solutions W1-mt_Mf-T-fYRLX-s1

  1. True · Dissolving spreads the solid into pieces too tiny to see. Hidden is not the same as gone.
  2. It dissolved into the water · The powder mixed completely into the water and can no longer be seen. It dissolved.
  3. No, the soil bits are still visible · Cloudy water with bits settling at the bottom means the soil never mixed completely in, so it did not dissolve.
  4. The pepper did not dissolve · The pepper specks are still visible, so the pepper never mixed completely into the water.
  5. Warm it so the water evaporates · The powder is dissolved, so a filter cannot catch it. Evaporating the water leaves the powder behind as a solid.
  6. Let the water evaporate away · As the water evaporates and turns to vapor, the salt is left behind in the container.
  7. A mixture · The sand never dissolved, so you can still see separate parts. That makes it a mixture, not a solution.
  8. 3 · Salt water, sugar water, and drink-powder water are clear solutions. The sand water still shows bits, so it is a mixture.
  9. Dissolved salt slips through with the water · In a solution the salt is dissolved into pieces far too small for filter paper to trap, so it passes through with the water.
  10. Because the mud never dissolved · A filter traps only solid bits that never dissolved. The mud stayed as separate bits, so the paper could hold it back.
Worksheet · LightMySky