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Year 9 Science — Solutes, solvents and solutions

Name the solute and the solvent in a solution, tell a saturated solution from an unsaturated one, and say how temperature changes what will dissolve.

Name: ________________________

  1. 1.Why does dissolved oxygen matter in a pond?

    • a) It keeps the water from freezing in winter
    • b) It makes the water taste better
    • c) It is what sustains the plants, fish and other organisms living in the water
    • d) It stops other gases from dissolving in the water

  2. 2.Are the gases dissolved in pond water a uniform or a non-uniform mixture?

    • a) Uniform, because the gases dissolve evenly through the water
    • b) Non-uniform, because gases are lighter than water and float to the top
    • c) Non-uniform, because a gas dissolved in a liquid can be seen bubbling
    • d) Uniform, because gases have no volume of their own

  3. 3.Match each word to what it names.

    • Solute
    • Solvent
    • Solution
    • Solubility
    • the substance that dissolves
    • the most solute a fixed quantity of solvent will take at a given temperature
    • the uniform mixture the two of them make
    • the substance that does the dissolving

  4. 4.Each sip of a homemade oral rehydration solution tastes the same as the last. Why?

    • a) The water dilutes both of them until neither can be tasted
    • b) The sugar and salt cancel out each other's taste
    • c) The sugar and salt are evenly distributed through the whole of the water
    • d) The sugar settles at the bottom and the salt stays at the top

  5. 5.Alcohol and water are mixed, with rather more water than alcohol. Which is the solute?

    • a) Neither, because two liquids cannot form a solution
    • b) The water, because it is a liquid
    • c) Both, because liquids mixed together are both solutes
    • d) The alcohol, because it is the one present in the smaller amount

  6. 6.In a glass of salt water, what is the water called? Give the one word.

  7. 7.Each of these has been stirred into water. Sort them by whether the result is even throughout.

    Groups: Uniform mixture · Non-uniform mixture

    • Sawdust in water
    • Sand in water
    • Salt in water
    • Chalk powder in water

  8. 8.The greatest amount of solute a fixed quantity of solvent will dissolve at a particular temperature has a one-word name. What is it?

Answer key — Year 9 Science — Solutes, solvents and solutions

  1. 1. c) It is what sustains the plants, fish and other organisms living in the water
  2. 2. a) Uniform, because the gases dissolve evenly through the water
  3. 3. Solute → the substance that dissolves; Solvent → the substance that does the dissolving; Solution → the uniform mixture the two of them make; Solubility → the most solute a fixed quantity of solvent will take at a given temperature
  4. 4. c) The sugar and salt are evenly distributed through the whole of the water
  5. 5. d) The alcohol, because it is the one present in the smaller amount
  6. 6. solvent
  7. 7. Salt in water → Uniform mixture; Sand in water → Non-uniform mixture; Sawdust in water → Non-uniform mixture; Chalk powder in water → Non-uniform mixture
  8. 8. solubility