Question

What is the concentration, in ppb, of sodium chloride in a solution where 23 g of NaCl are dissolved into 1880 g of water? Your answer should have two significant figures. Provide your answer below:

Answer 1

The concentration of sodium chloride in a solution with 23 g of NaCl dissolved into 1880 g of water is 12×106 ppb, or 12 million ppb, when rounded to two significant figures.

Step-by-step explanation:

To calculate the concentration of sodium chloride (NaCl) in parts per billion (ppb), we need to first find the total mass of the solution which is the mass of the NaCl plus the mass of the water. Then, the concentration in ppb is found by taking the mass of the NaCl, dividing by the total mass of the solution, and then multiplying by 109 (since ppb stands for parts per billion).

The total mass of the solution is 23 g + 1880 g = 1903 g. Now, we calculate the concentration in ppb:

Concentration (ppb) = (mass of NaCl / total mass of solution) × 109

Concentration (ppb) = (23 g / 1903 g) × 109 = 1.21×107 ppb

This result should be rounded to two significant figures: 12×106 ppb or 12 million ppb.