Final answer:
To reach the WHO's acceptable limit of 0.01 ppm for arsenic, 1.2 L of water containing 4.3 ppm must be diluted to a total volume of 516 L.
Step-by-step explanation:
To calculate to what volume you would need to dilute 1.2 L of water containing 4.3 ppm arsenic to reach the acceptable limit, you'll need to know the acceptable limit for arsenic in water. The World Health Organization (WHO) has set a limit of 10 micrograms per liter (10 μg/L or 0.01 ppm) for arsenic in drinking water. Using this standard, we can determine the amount of water needed to dilute the original arsenic concentration to an acceptable level.
First, convert the arsenic concentration from ppm to mg/L: 4.3 ppm arsenic is equivalent to 4.3 mg/L since 1 ppm is akin to 1 mg/L in water, given its approximate density of 1 g/mL. The original amount of arsenic in 1.2 L is therefore 4.3 mg/L * 1.2 L = 5.16 mg. To achieve an arsenic concentration of 0.01 ppm or 0.01 mg/L, you can set up a proportion:
(Original Concentration) / (Original Volume) = (Desired Concentration) / (Desired Volume)
(4.3 mg/L) / (1.2 L) = (0.01 mg/L) / (x L)
Solve for x to find the desired volume:
(4.3 * 1.2) / 0.01 = x
x = 516 L
To reduce arsenic levels to the acceptable limit, you would need to dilute the original 1.2 L of water to a total volume of 516 L.