Question

An analysis showed there is 0.001 mol/L OH in a NaOH

solution. Suppose the solution is 1 kg. Then What will be the
concentration of NaOH in ppm? ___ ppm

Answer 1

40 ppm of NaOH

Step-by-step explanation:

ppm is nothing but the parts per million and it is represented as 1 mg solute per kg of solution.

Here, number of moles of solute (NaOH) can be found as 0.001 mol / L, so we can find the amount of solute as,

Moles =
`$(mass of the solute )/( molar mass)`

0.001 mol / L =
`$( mass of the solute)/(40 g/ mol)`

0.001 × 40 = 0.04 g of solute

1 g = 1000 mg

0.04 g = 40 mg

In 1 kg of solution 40 mg of solvent is present.

So the concentration of NaOH is 40 ppm.