If a dissolved chemical in water has a concentration of 30 ppm by mass, how much water is required for 1 gram of this chemical?

If a dissolved chemical in water has a concentration of 30 ppm by mass, how much water is required for 1 gram of this chemical?

• A. 25 L
• B. 30 L
• C. 33.3 L
• D. 37.5 L

Answer: (C)

To determine how much water is required for 1 gram of a chemical with a concentration of 30 ppm by mass, it's important to understand what parts per million (ppm) implies in this context. A concentration of 30 ppm means that there are 30 grams of the chemical in 1 million grams of the solution (which includes both the chemical and the water). In practical terms, if we have 1 gram of the dissolved chemical, we need to find out how much solvent (water) it would be in a solution that maintains this 30 ppm concentration. First, we can set up the relationship based on the definition of ppm: - If 30 grams of the chemical corresponds to 1,000,000 grams of solution, then for 1 gram of the chemical, the total mass of the solution (chemical + water) can be calculated using proportions. If 30 g of the chemical corresponds to 1,000,000 g of solution, then: \[ 1 g \text{ of chemical} = \frac{1,000,000 g}{30} \approx 33333.33 g \text{ of solution} \] The amount of water is the total mass of the solution minus the mass

To determine how much water is required for 1 gram of a chemical with a concentration of 30 ppm by mass, it's important to understand what parts per million (ppm) implies in this context. A concentration of 30 ppm means that there are 30 grams of the chemical in 1 million grams of the solution (which includes both the chemical and the water).

In practical terms, if we have 1 gram of the dissolved chemical, we need to find out how much solvent (water) it would be in a solution that maintains this 30 ppm concentration.

First, we can set up the relationship based on the definition of ppm:

• If 30 grams of the chemical corresponds to 1,000,000 grams of solution, then for 1 gram of the chemical, the total mass of the solution (chemical + water) can be calculated using proportions.

If 30 g of the chemical corresponds to 1,000,000 g of solution, then:

[

1 g \text{ of chemical} = \frac{1,000,000 g}{30} \approx 33333.33 g \text{ of solution}

]

The amount of water is the total mass of the solution minus the mass