Question

supposedly gold nugget is tested to determine its density. It is found to displace 19.3 mL of water and has a mass of 371 grams. Could the nugget be made of gold?

Calculate to the correct number Of significant figures.

- 89.3 x 77.0 x 0.08

- (5.01 x 105) (7.8 x 10 2)

Answer 1

CONCEPT: The specific gravity of gold is 19.32. If the specific gravity of gold nugget comes out to be the same then it is gold nugget. Otherwise not.

specific gravity = mass / volume

volume = volume of water displaced

volume of water = mass of water displaced / density

density of water = 1g/cm³

threfore volume of water = 19.3 / 1 = 19.3mL (1cm³ = 1mL)

specific gravity of gold = mass / volume

specific gravity of gold = 371 / 19.3 = 19.223g/mL

since specific gravity is approximately equal to 19.3 we can say it is a gold nugget

(B) 89.3 x 77.0 x 0.08 = 550.088

The decimal points in answer must be equal to the one that has least decimal points.

Hence the correct presentation of answer is 550.0

89.3 x 77.0 x 0.08 = 550.0

There are four decimal places

(5.01 x 10⁵) (7.8 x 10 ²) = 39.078 X 10 ⁷

(5.01 x 10⁵) (7.8 x 10 ²) = 39.0 X 10 ⁷

^{Explained above}