A 375 g sample of well water is found to contain 17.0 mg of lead. How much lead (in parts per million) is in the well water? Round to the nearest tenth. Don't forget the unit.
1 ppm = 1 part/1,00,000 parts.
So you convert 17 mg/375g to g/10^6 g.
17 mg = 0.017 g
The easiest way to do this I think is to multiply numerator and denominator by some numbers such that 375 becomes 1,000,00. That's asking 375g x ? = 1,000,000g and calculate ? as 1,000,000/375 = 2,666.7
Now 0.017g x 2,666.7 = approximately 45.
Another way of doing it, and it may be a little clearer this way, is
17 mg/375g = 0.017g/375g = 4.53E-5gPb/1 gH2O. Multiply both numerator and denominator by 1E6 to convert to g/1,000g or ppm. Then 4.53E-5*1E6/1E6 = 45.3 ppm.
ffr
To calculate the concentration of lead in parts per million (ppm), you need to divide the mass of lead by the mass of the water sample and then multiply by 1,000,000.
First, convert the mass of lead to grams:
17.0 mg = 17.0 × 10⁻³ g
Next, calculate the concentration of lead in ppm:
PPM = (Mass of lead / Mass of water sample) × 1,000,000
= (17.0 × 10⁻³ g / 375 g) × 1,000,000
PPM = 45.3 ppm
So, the concentration of lead in the well water is approximately 45.3 ppm.
To find the concentration of lead in the well water in parts per million (ppm), we need to convert the mass of lead to the same units as the mass of the water sample.
First, let's convert the mass of lead from milligrams (mg) to grams (g):
17.0 mg = 17.0 × 10^(-3) g = 0.017 g
Next, we can calculate the concentration of lead in ppm using the formula:
ppm = (mass of substance / mass of solution) × 10^6
Mass of substance = 0.017 g
Mass of solution = 375 g
ppm = (0.017 g / 375 g) × 10^6
ppm = (0.00004533333) × 10^6
ppm ≈ 45.3
Therefore, the concentration of lead in the well water is approximately 45.3 parts per million (ppm).