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Year 9 Science — Density, and how to measure it

Calculate density from mass and volume, find the volume of an irregular solid by displacement, and say what heating does to density.

Name: ________________________

  1. 1.A measuring cylinder has bigger marks 20 mL apart, and there are 10 small divisions between the 20 mL and 40 mL marks. What is the smallest volume it can read, in millilitres? Answer with a number.

  2. 2.Put the steps for finding the volume of an oddly shaped stone back into order.

    • Tie the object with a thread and lower it slowly into the cylinder
    • Fill a measuring cylinder with water and record the initial volume
    • Subtract the initial volume from the final volume
    • Record the final volume once the level has risen

  3. 3.A stone sculpture has a mass of 225 g and a volume of 90 cm³. What is its density, in grams per cubic centimetre? Answer with a number.

  4. 4.An object has a mass of 400 g and a volume of 40 cm³. What is its density, in grams per cubic centimetre? Answer with a number.

  5. 5.Object B has a mass of 240 g and a volume of 60 cm³. What is its density, in grams per cubic centimetre? Answer with a number.

  6. 6.A closed box is 12 cm long, 5 cm wide and 4 cm high. What is its volume, in cubic centimetres? Answer with a number.

  7. 7.Water in a measuring cylinder forms a curved surface called the meniscus. Where should you take the reading for water?

    • a) At the bottom of the meniscus, looking down from above
    • b) Midway up the curve, from wherever you happen to be standing
    • c) At the bottom of the meniscus, with your eye level with it
    • d) At the top of the meniscus, with your eye level with it

  8. 8.A substance is heated. What generally happens to its density, and why?

    • a) It decreases, because the particles spread out so the volume grows while the mass stays the same
    • b) It increases, because heating adds energy and so adds mass
    • c) It decreases, because heating destroys some of the particles
    • d) It stays the same, because density does not depend on temperature

Answer key — Year 9 Science — Density, and how to measure it

  1. 1. 2
  2. 2. 1. Fill a measuring cylinder with water and record the initial volume 2. Tie the object with a thread and lower it slowly into the cylinder 3. Record the final volume once the level has risen 4. Subtract the initial volume from the final volume
  3. 3. 2.5
  4. 4. 10
  5. 5. 4
  6. 6. 240
  7. 7. c) At the bottom of the meniscus, with your eye level with it
  8. 8. a) It decreases, because the particles spread out so the volume grows while the mass stays the same