Question

Three items were bought at a car boot sale.

Item A
Mass = 42 grams
Volume = 2 cm
Item B
Mass = 87.5 grams
Volume 5 cm3
Item C
Mass = 147 grams
Volume = 7 cm3
=

The density of platinum is approximately 21 grams per cmº.
Which of the items cannot be platinum?
You must show your working.

Answer 1

Answer: Multiply the density with the volume. You get 2418.2 grams or 2.4182 kilograms

Explanation:

Answer 2

Item B

Explanation:

A:

density = mas/volume = 42 g / 2 cm^3 = 21 g/cm^3

This may be platinum.

B.

density = mass/volume = 87.5 g / 5 cm^3 = 17.5 g/cm^3

This cannot be pure platinum.

C.

density = mass/volume = 147 g / 7 cm^3 = 21 g/cm^3

This may be platinum.

Answer: Item B