Question

The molarity of C29H6O in winter rainwater is 5.6 nM. Find the concentration in ppb.

Answer 1

Given:

Molarity of C29H6O in rainwater = 5.6 nM = 5.6 × 10⁻⁹ M

To Find:

The concentration of C29H6O in ppb.

Calculation:

- The no of moles of C29H6O in 1 litre solution = 5.6 × 10⁻⁹

- The molar mass of C29H6O = 370 gm

- The mass of 5.6 × 10⁻⁹ moles of C29H6O = 5.6 × 10⁻⁹ × 370

w = 2072 × 10⁻⁹ gm

- The mass of solution, W = 1000 gm

- ppb concentration = (w/W) × 10⁹

⇒ ppb concentration = (2072 × 10⁻⁹/1000) × 10⁹

⇒ ppb concentration = 2.072 ppb

- So, the concentration of C29H6O is 2.072 ppb.