Final answer:
To reach the toxic level of 0.2 g of F−, a 70-kg person would need to consume approximately 285.71 liters of fluoridated drinking water in one day.
Step-by-step explanation:
To determine how many liters of fluoridated drinking water a 70-kg person would have to consume in one day to reach the toxic level of 0.2 g of F−, we need to find the amount of F− ions ingested from 1 liter of water and then divide the toxic level by this amount.
Given that the concentration of F− ions in fluoridated water is 1 mg/L, or 0.001 g/L, and the person's body weight is 70 kg, we can calculate the number of liters of water needed using the equation:
Number of liters = Toxic level / (Concentration of F− ions per liter × Body weight)
Plugging in the values, we get:
Number of liters = 0.2 g / (0.001 g/L × 70 kg) = 285.71 L
Therefore, a 70-kg person would need to consume approximately 285.71 liters of fluoridated drinking water in one day to reach the toxic level of 0.2 g of F−.