What is the concentration in parts per million of DDT in each of the following?

Part 1 of 2

0.034 mg in 1800. g plankton. Be sure your answer has the correct number of significant figures.
Note: Reference the SI prefixes table for additional information.

ppm DDT

The first step is to convert the mass of DDT from milligrams to grams:

0.034 mg = 0.000034 g

Next, we will calculate the concentration in parts per million (ppm):

Concentration (ppm) = (mass of DDT / total mass of plankton) * 1,000,000

Concentration (ppm) = (0.000034 g / 1800 g) * 1,000,000

Concentration (ppm) = (1.89 x 10^-8) * 1,000,000

Concentration (ppm) = 0.0189 ppm

Therefore, the concentration of DDT in 0.034 mg in 1800 g plankton is 0.0189 ppm.