Science 7 · Unit 8: Changes to materials · Cambridge Lower Secondary Science Stage 7

Questions

1. 1. What is the curved surface of a liquid in a measuring cylinder called?

   • the meniscus
   • the scale
   • the burette
   • the beaker
   Check

2. 2. Where do you read the volume in a measuring cylinder?

   • at the bottom of the curved surface (meniscus)
   • at the top of the curve, where it touches the glass
   • at the bottom of the cylinder
   • anywhere on the liquid
   Check

3. 3. Measuring cylinder B. Read the volume from the bottom of the meniscus. What is the volume of liquid?

   • 35 cm³
   • 25 cm³
   • 20 cm³
   • 30 cm³
   Check

4. 4. Measuring cylinder C. Read the volume from the bottom of the meniscus. What is the volume of liquid?

   • 30 cm³
   • 46 cm³
   • 40 cm³
   • 36 cm³
   Check

5. 5. Measuring cylinder D. Read the volume from the bottom of the meniscus. What is the volume of liquid?

   • 18 cm³
   • 20 cm³
   • 12 cm³
   • 10 cm³
   Check

6. 6. Measuring cylinder E. Read the volume from the bottom of the meniscus. What is the volume of liquid?

   • 57 cm³
   • 47 cm³
   • 43 cm³
   • 50 cm³
   Check

7. 7. Where is zero on a burette scale?

   • at the top
   • at the bottom
   Check

8. 8. The liquid in a burette is between the 30 and 40 marks, at the fifth small mark below 30. What is the reading?

   • 45 cm³
   • 65 cm³
   • 35 cm³
   • 25 cm³
   Check

9. 9. What is made when an acid is neutralised by an alkali?

   • more acid
   • a salt and water
   • hydrogen gas
   • an oxide only
   Check

10. 10. What colour is universal indicator when an acid is exactly neutralised?

    • green
    • red
    • blue
    • purple
    Check

11. 📖 This question is about a text that students read in the app.

    11. The student did not wear goggles "because they hurt my nose". Why is this unsafe?

    • Acid or alkali could splash into their eyes.
    • Goggles are only for heating.
    • Goggles make the reaction slower.
    • The teacher could not see them.
    Check

12. 📖 This question is about a text that students read in the app.

    12. The student was told to use 0.5 mol/dm³ acid, but used 1.0 mol/dm³ hydrochloric acid from the teacher's shelf. Why was this wrong?

    • The bottle was too small.
    • It was weaker, so it would not react.
    • It was the wrong colour.
    • It was a stronger acid that they had not been told to use, which is less safe.
    Check

13. 📖 This question is about a text that students read in the app.

    13. The student filled a beaker about half full of acid. What should they have done?

    • Use the whole bottle.
    • Measure a small, exact volume with a measuring cylinder.
    • Fill the beaker to the top.
    • Pour in acid without measuring.
    Check

14. 📖 This question is about a text that students read in the app.

    14. The student poured half a bottle of universal indicator into the acid. What should they have done?

    • Add the whole bottle.
    • Add just a few drops.
    • Add the indicator to the alkali bottle.
    • Add no indicator.
    Check

15. 15. The student added all the alkali at once, and it went straight past green to blue. What should they do instead?

    • Add the alkali a little at a time, stirring and watching the indicator.
    • Add more acid to make it red again.
    • Guess how much alkali to use.
    • Tip it into a bigger beaker.
    Check

16. 16. Which piece of equipment lets you add the alkali a little at a time and measure how much you add?

    • a beaker
    • a measuring cylinder
    • a burette
    • a conical flask
    Check

17. 📖 This question is about a text that students read in the app.

    17. The student "guessed how much alkali to use" because it was taking too long. Why is this a problem?

    • Guessing makes the reaction faster.
    • Guessing is always accurate.
    • The solution would probably not be exactly neutral.
    • The indicator would stop working.
    Check