Year 8 Science — Density, and how to measure it

1.Object A has a mass of 200 g and a volume of 40 cm³. What is its density, in grams per cubic centimetre? Answer with a number.

2.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.

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

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

4.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.

5.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.

6.Water is at its densest at 4 °C. As it cools further and turns to ice at 0 °C, what happens?

• a) The mass decreases, which is what makes ice float
• b) The density stays exactly the same, since freezing is a physical change
• c) The particles pack closer together, so ice is denser and would sink but for the surface tension
• d) The particles arrange themselves so as to take up more space, so ice is less dense and floats

7.Water in a measuring cylinder stands at 40 mL. A metal key is lowered in and the level rises to 47 mL. What is the key's volume, in cubic centimetres? Answer with a number.

8.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.