Q: Which of the following correctly defines parts per million (ppm) in terms of mass?

$$\text{ppm} = \frac{\text{g solute}}{\text{g solution}} \times 10^6$

Q: A 1.0 kg sample of soil contains 2.0 mg of a pesticide. What is the concentration of the pesticide in ppm?

$$2.0$$ ppm$$=\frac{2.0\,\text{mg}}{1000\,\text{g}} \times 10^6$ = 2.0$$ ppm

Q: Which formula would you use to calculate the concentration in parts per billion (ppb) by volume?

$$\text{ppb} = \frac{\text{ml solute}}{\text{ml solution}} \times 10^9$

Q: A water sample contains the pollutant chlorobenzene with a concentration of 16 ppm (by volume). What volume of this water contains $$5.01 \times 10^2$ mL of chlorobenzene?

$$3.13 \times 10^7$ mL$$=\frac{5.01 \times $$10^2$$}{16} \times $$10^6$$

Q: If a solution contains 0.005 g of solute in 2.0 L of solution, what is the concentration in ppm? (Assume density of solution is 1.00 g/mL)

$$2.5$$ ppm$$=\frac{0.005}{2000} \times 10^6$

Question 1

Which of the following correctly defines parts per million (ppm) in terms of mass?

Accepted Answer

$$	ext{ppm} = \frac{	ext{g solute}}{	ext{g solution}} 	imes 10^6$

Question 2

A 1.0 kg sample of soil contains 2.0 mg of a pesticide. What is the concentration of the pesticide in ppm?

Accepted Answer

$$2.0$$ ppm$$=\frac{2.0\,	ext{mg}}{1000\,	ext{g}} 	imes 10^6$ = 2.0$$ ppm

Question 3

Which formula would you use to calculate the concentration in parts per billion (ppb) by volume?

Accepted Answer

$$	ext{ppb} = \frac{	ext{ml solute}}{	ext{ml solution}} 	imes 10^9$

Question 4

A 2.4 L sample of an aqueous solution contains 0.012 mL of NH$$_3. $$What is the concentration of NH$$_3 in $$ppb?

Accepted Answer

$$5,000$$ ppb

Question 5

A 5.12 L sample of solution contains 0.239 g of potassium sulfate (K$$_2SO$_4). If $$the density of the solution is 1.30 g/mL, what is the concentration of K$$_2SO$_4 in $$ppm?

Accepted Answer

$$2,283$$ ppm

Question 6

Calculate the concentration in ppb for a solution containing 0.91 mg of caffeine in 131 mL of solution.

Accepted Answer

$$0.00069$$ ppb

Question 7

Glucose makes up about 0.102% by mass of human blood. What is this concentration in ppm?

Accepted Answer

$$102$$ ppm

Question 8

The average human body contains about 5,000 grams of blood. If the amount of arsenic in blood is 0.86 ppb, what mass of arsenic is present in the body?

Accepted Answer

$$4.3 	imes 10$$^{-3}$$ g

Question 9

A water sample contains the pollutant chlorobenzene with a concentration of 16 ppm (by volume). What volume of this water contains $$5.01 	imes 10^2$ mL of chlorobenzene?

Accepted Answer

$$3.13 	imes 10^7$ mL$$=\frac{5.01 	imes $$10^2$$}{16} 	imes $$10^6$$

Question 10

Which of the following best describes the difference between ppm and ppb?

Accepted Answer

ppm is parts per million, while ppb is parts per billion; ppb is $$10^3$$ times smaller than ppm

Question 11

If a solution contains 0.005 g of solute in 2.0 L of solution, what is the concentration in ppm? (Assume density of solution is 1.00 g/mL)

Accepted Answer

$$2.5$$ ppm$$=\frac{0.005}{2000} 	imes 10^6$

Question 12

A sample of water contains 0.0002 g of lead in 500 mL. What is the concentration of lead in ppb?

Accepted Answer

$$400$$ ppb

Question 13

Which of the following is a correct real-world application of ppm?

Accepted Answer

Measuring the concentration of carbon monoxide in air pollution

Question 14

A solution contains 0.002 g of mercury in 1.5 L of water. What is the concentration in ppm? (Assume density = 1.00 g/mL)

Accepted Answer

$$1.33$$ ppm

Question 15

If a solution has a concentration of 0.0001 ppm, what is this value in ppb?

Accepted Answer

$$0.1$$ ppb

Question 16

A chemist needs to prepare 250 mL of a solution with a concentration of 10 ppm of sodium chloride. How many milligrams of sodium chloride are required?

Accepted Answer

$$2.5 mg$$

Question 17

Which of the following statements about ppm and ppb is correct?

Accepted Answer

ppb is used for more dilute solutions than ppm

Question 18

A sample contains 0.003 g of solute in 3.0 L of solution. What is the concentration in ppb? (Assume density = 1.00 g/mL)

Accepted Answer

$$1$$ ppb

Question 19

A scientist finds that a water sample contains 0.0008 g of copper in 2.0 L. What is the concentration in ppm?

Accepted Answer

$$0.4$$ ppm

Parts per Million (ppm) and Parts per Billion (ppb): Calculations and Applications in Solution Chemistry

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