KS2 Science Quiz - Mixing and Dissolving (Questions)

In KS2 Science children will conduct experiments involving solvents, solutes and suspensions. They will try mixing different materials and see which 'mix' (sugar dissolving in water for example) and which don't.

Mixtures are created by combining materials together. Solids, liquids, and gases can be mixed together. You will have seen some materials dissolving when you've added them to water. Sugar dissolves in water. It is a solute and water is the solvent. The mix of water and sugar is called a solution. Some other materials, like sand for example, do not dissolve in water. Instead the particles are spread out when you shake the mixture. This is called a suspension. The particles in a suspension will eventually settle to the bottom.

What's the difference between a solvent, a solute and a solution? See how much you can remember from your investigations by trying this Mixing and Dissolving quiz.

1. What is a mixture?
[ ] A pure element
[ ] A material resulting from a chemical reaction
[ ] A chemical compound
[ ] The combination of two or more materials (substances)
2. If you mixed sand, sugar and water, which material would dissolve?
[ ] Sand
[ ] Sugar
[ ] Sand and sugar
[ ] Neither sand nor sugar
3. Sieving would separate which of these mixtures?
[ ] Salt and water
[ ] Sand and salt
[ ] Sand and gravel
[ ] Soil and salt
4. When a material is dissolved, what does it make?
[ ] A new substance or material
[ ] A gas
[ ] A force
[ ] A solution
5. Which of these processes would you use to separate salt from the water in which it has been dissolved?
[ ] Filtration
[ ] Evaporation
[ ] Sieving
[ ] Suspension
6. Which of these would help sugar dissolve more quickly in coffee?
[ ] Using hot coffee
[ ] Using cold coffee
[ ] Using cold sugar
[ ] Not disturbing the sugar as it dissolves
7. What is a suspension?
[ ] A mixture created by combining two liquids
[ ] A mixture of two gases
[ ] A clear solution
[ ] A mixture of a solid and liquid, where the solid will not dissolve in the liquid
8. What is a solvent?
[ ] The material which has been dissolved in a liquid
[ ] The liquid in which a material has been dissolved
[ ] The particles remaining in suspension
[ ] The material left after evaporation
9. Which of these materials would not dissolve in water?
[ ] Icing sugar
[ ] Gelatine crystals
[ ] A candle
[ ] Sea salt
10. Which of the following statements is not true?
[ ] There is no limit to the amount of a particular material that can be dissolved by a liquid
[ ] Hot liquid will be able to dissolve more of the solute
[ ] Water can dissolve more of some materials than of other materials
[ ] Different variables affect how much material a solvent can dissolve

 

KS2 Science Quiz - Mixing and Dissolving (Answers)
1. What is a mixture?
[ ] A pure element
[ ] A material resulting from a chemical reaction
[ ] A chemical compound
[x] The combination of two or more materials (substances)
The name should have given it away! Combination means joined together or mixed
2. If you mixed sand, sugar and water, which material would dissolve?
[ ] Sand
[x] Sugar
[ ] Sand and sugar
[ ] Neither sand nor sugar
Water will dissolve sugar but will not dissolve sand
3. Sieving would separate which of these mixtures?
[ ] Salt and water
[ ] Sand and salt
[x] Sand and gravel
[ ] Soil and salt
A very fine sieve would separate the coarsest sand from the salt, but it would also allow fine sand to pass through its holes
4. When a material is dissolved, what does it make?
[ ] A new substance or material
[ ] A gas
[ ] A force
[x] A solution
Solids can be dissolved in liquids, creating a solution - a solution is not a new substance, however; it is a mixture of two or more materials or substances
5. Which of these processes would you use to separate salt from the water in which it has been dissolved?
[ ] Filtration
[x] Evaporation
[ ] Sieving
[ ] Suspension
The water can evaporate but salt cannot so it will be left behind
6. Which of these would help sugar dissolve more quickly in coffee?
[x] Using hot coffee
[ ] Using cold coffee
[ ] Using cold sugar
[ ] Not disturbing the sugar as it dissolves
Stirring, using smaller particles (by crushing, if necessary), and heating the liquid all help materials to dissolve more quickly
7. What is a suspension?
[ ] A mixture created by combining two liquids
[ ] A mixture of two gases
[ ] A clear solution
[x] A mixture of a solid and liquid, where the solid will not dissolve in the liquid
A good example of a suspension is a jar of muddy water - if you look closely, you can see particles suspended (floating) in the water
8. What is a solvent?
[ ] The material which has been dissolved in a liquid
[x] The liquid in which a material has been dissolved
[ ] The particles remaining in suspension
[ ] The material left after evaporation
When salt is dissolved into water, the salt is a solute, the water is the solvent and the mixture is called a solution
9. Which of these materials would not dissolve in water?
[ ] Icing sugar
[ ] Gelatine crystals
[x] A candle
[ ] Sea salt
Although a candle would melt in very hot water, wax will not dissolve in water - remember that melting and dissolving are not the same process
10. Which of the following statements is not true?
[x] There is no limit to the amount of a particular material that can be dissolved by a liquid
[ ] Hot liquid will be able to dissolve more of the solute
[ ] Water can dissolve more of some materials than of other materials
[ ] Different variables affect how much material a solvent can dissolve
A solution in which no more material can be dissolved is called 'saturated'