Question

In clinical applications, the unit parts per million (ppm) is used to express very small concentrations of solute, where 1 ppm is equivalent to 1 mg of solute per 1 L of solution. Calculate the concentration in parts per million for each of the solutions.There is 43 μg of calcium in a total volume of 87 mL .concentration of calcium: _________ppm There is 0.91 mg of caffeine in a total volume of 105 mL .concentration of caffeine: _________ppm There is 0.47 mg of trace particles in a total volume of 95 dL .concentration of trace particles: ___________

Answer 1

Answer & Procedure

To solve this problem you will need to transform all the concentrations to the equivalence of ppm, which is 1 mg of solute per 1 L of solution.

Calcium: There are 43 μg of calcium in a total volume of 87 mL.

`\frac{43\mu g}{87\text{ mL}}\frac{1\text{ mg}}{1000\text{ }\mu g}\frac{1000\text{ mL}}{1\text{ L}}=0.49(mg)/(L)=0.49\text{ ppm}`

Caffeine: There is 0.91 mg of caffeine in a total volume of 105 mL.

`\frac{0.91\text{ mg}}{105\text{ mL}}\frac{1000\text{ mL}}{1\text{ L}}=8.67(mg)/(L)=\text{ 8.67 ppm}`

Trace particles: There is 0.47 mg of trace particles in a total volume of 95 dL.

`\frac{0.47\text{ mg}}{95\text{ dL}}\frac{10\text{ dL}}{1\text{ L}}=0.049(mg)/(L)=0.049\text{ ppm}`