Question

Water from systems where sanitary, physical, operating defects or other special hazards are known to exist must be chlorinated to specified bacterial levels. Residual should be at least how many ppm?

Answer 1

To achieve a 3.0 ppm chlorine concentration in a 21,200 kg (5,000-gallon) pool, 63.6 grams of chlorine is required.

Step-by-step explanation:

When chlorinating water to eliminate known hazardous contaminants, a certain residual level of chlorine must be maintained. In general, water systems should achieve a chlorine residual of at least 1 ppm, but the exact requirement can vary based on regulations and the specific conditions of the water system. However, if we want to achieve a chlorine concentration of 3.0 ppm in a 5,000-gallon pool (which is equivalent to 21,200 kg of water), we can calculate the mass of chlorine to be added as follows:

Firstly, know that 1 ppm is equivalent to 1 milligram of substance per kilogram of water (mg/kg). To reach a concentration of 3.0 ppm in 21,200 kg of water, you would need:

3.0 ppm * 21,200 kg = 63,600 mg of chlorine.

Since there are 1,000 mg in a gram, this can be converted to grams:

63,600 mg / 1,000 = 63.6 grams of chlorine.

Therefore, to achieve a chlorine concentration of 3.0 ppm in a 5,000-gallon pool, one must add 63.6 grams of chlorine.