Science 8 · Unit 2: Properties of materials · Cambridge Lower Secondary Science Stage 8

Questions

1. 1. What is a substance that will not dissolve in water?

   • concentrated
   • insoluble
   • saturated
   • soluble
   Check

2. 2. Solutions A and B have the same volume of solvent, but A has more solute particles. What is A?

   • more concentrated
   • less soluble
   • more dilute
   • insoluble
   Check

3. 3. Sofia adds copper sulfate until no more will dissolve. What has she made?

   • a saturated solution
   • an insoluble solution
   • a filtrate
   • a dilute solution
   Check

4. 4. Marcus adds 50 cm³ of water to a salt solution. What has he done?

   • concentrated it
   • saturated it
   • diluted it
   • filtered it
   Check

5. 5. What is solubility?

   • how much of a solute can dissolve in a solvent
   • how heavy a solid is
   • how fast a liquid boils
   • the colour of a solution
   Check

6. 6. Zara added A 3, B 1, C 2 spatulas until no more dissolved. Which solute was most soluble?

   • C
   • they were all the same
   • B
   • A
   Check

7. 7. Zara: A 3, B 1, C 2. Which was least soluble?

   • B
   • C
   • A
   • they were all the same
   Check

8. 8. Look at the test tubes. Zara got A 3, B 1, C 2 spatulas; Arun got A 9, B 3, C 6. Do Arun's results agree with Zara's?

   • Yes, the numbers are identical.
   • Yes, the order is the same - he used more water.
   • No, they are opposite.
   • No, Arun was wrong.
   Check

9. 9. Look at the test tubes. Why could Arun dissolve more spatulas than Zara?

   • He used a different solute.
   • He stirred less.
   • He used more water in his test tubes.
   • His spatula was smaller.
   Check

10. 10. Look at Marcus's test tubes. He got 3 spatulas for every solute. Why can't his results be used to compare the solutes?

    • All solutes are equally soluble.
    • He used a magnet.
    • He used the same water in each.
    • He used different volumes of water in each tube.
    Check

11. 11. How can Arun make 100 cm³ of a solution half as concentrated as X?

    • mix 100 cm³ of X with 100 cm³ of water
    • mix 50 cm³ of X with 50 cm³ of water
    • use 100 cm³ of X only
    • mix 25 cm³ of X with 75 cm³ of water
    Check

12. 12. How can Arun make 100 cm³ of a solution a quarter as concentrated as X?

    • add 4 cm³ of X
    • mix 25 cm³ of X with 75 cm³ of water
    • mix 75 cm³ of X with 25 cm³ of water
    • mix 50 cm³ of X with 50 cm³ of water
    Check

13. 13. What helps make solutions up accurately?

    • using a measuring cylinder and reading at eye level
    • using any cup
    • guessing volumes
    • filling to the brim
    Check

14. 14. Copper sulfate dissolves in water. What is it?

    • saturated
    • a solvent
    • soluble in water
    • insoluble in water
    Check

15. 15. Does a dilute solution have more or fewer solute particles in a volume than a concentrated one?

    • more
    • fewer
    Check

16. 16. Look at the table. How much copper sulfate dissolves in 100 g of water at 20 °C?

    • 32 g
    • 7 g
    • 74 g
    • 36 g
    Check

17. 17. Look at the table. How much potassium chlorate would dissolve in 200 g of water at 20 °C?

    • 14 g
    • 7 g
    • 3.5 g
    • 207 g
    Check

18. 18. Look at the table. How much sodium chloride would dissolve in 50 g of water at 20 °C?

    • 36 g
    • 18 g
    • 86 g
    • 72 g
    Check

19. 19. Look at the table. Which salt is the most soluble at 20 °C?

    • calcium chloride
    • potassium chlorate
    • copper sulfate
    • sodium chloride
    Check

20. 20. 204 g of sugar dissolves in 100 g of water at 20 °C. How much dissolves in 250 g of water at 20 °C?

    • 204 g
    • 816 g
    • 454 g
    • 510 g
    Check