Question

An abondoned stone quarry has filled with water to an average depth of 22.50 meters and a surface are of 2.887 km^2. In your lab you analyze five water samples from the quarry and conclude that each liter of quarry water contains 18.3pg of mercury on average.

(a.) What is the volume (in m^3) of the water in the quarry?

(b.) What is the total mass of mercury (in kg) in the quarry?

Answer 1

(a) The volume of water in the quarry is 6.496 x 10⁷ m³.

(b) The total mass of mercury is 1.19 x 10⁻³ kg.

Step-by-step explanation:

(a) The volume of water can be calculated like:

Volume = depth x surface

In order to have coherence between units we will use proportions to transform km² to m².

`2.887km^(2) .((10^(3)m)^(2) )/((1km)^(2) ) =2.887 * 10^(6) m^(2)`

Then,

Volume = 22.50 m x 2.887 x 10⁶ m² = 6.496 x 10⁷ m³

(b) We can find out the total mass of mercury using proportions. We will need these relations:

1 L = 10⁻³ m³

1 pg = 10⁻¹² g

1 kg = 10³ g

`6.496*10^(7) m^(3) (H_(2)O).(1L(H_(2)O))/(10^(-3)m^(3)(H_(2)O)  ) .(18.3pg(Hg))/(1L(H_(2)O)) .(10^(-12)g(Hg) )/(1pg(Hg)) .(1kg(Hg))/(10^(3)g(Hg) ) =1.19* 10^(-3) kg(Hg)`