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

Item B

Explanation:

item b is too light

Answer 2

9514 1404 393

Answer:

Item B

Explanation:

The mass of platinum with the given volumes would be ...

A: (2 cm³)(21 g/cm³) = 42 g . . . matches the given mass

B: (5 cm³)(21 g/cm³) = 105 g . . . greater than the given mass, which is not platinum

C: (7 cm³)(21 g/cm³) = 147 g . . . matches the given mass

__

Item B is too light to be platinum.