The mass of magnesium ions in 1 kg of sea water is 1.3 g. The concentration in parts per million (ppm) is
a 1.3x10^6
b 1.3x10^3
c 1.3x10^-3

I dont understand how to do this question. Help would be much appreciated!

1300 ppm

Explanation:

for ppm, calculate fractional ration =(part/total) and multiply by 1 x 10⁶ => ppm

for ppb, calculate fractional ration =(part/total) and multiply by 1 x 10⁹ => ppb

Parts Per Million (ppm)

Given 1.36g in 1Kg (=1000g) => fractional ratio = (1.3g/1000g)(10⁶) = 1300 ppm

Parts Per Billion (ppb)

or if ppb is needed do the same calculation but multiply by 10⁹ ... That is,

Given 1.36g in 1Kg (=1000g) => fractional ratio = (1.3/1000g)(10⁹) = 1300000 ppb = 1.3 x 10⁶ ppb

Parts per Hundred (pph) is the same as percent (%) ... Calculate fractional ratio and then multiply by 100%

Given 1.36g in 1Kg (=1000g) => fractional ratio = (1.3g/1000g)(100%) = 0.13%

elements make up everything, and they combine to make compounds.

the answer is c