How many capfuls of bleach to 1 gallon of water to make 100 ppm santizing solution?

To create a 100 ppm (parts per million) sanitizing solution using bleach, you typically need about 1/2 teaspoon of regular household bleach (which is approximately 5-6% sodium hypochlorite) per gallon of water. This is roughly equivalent to about 2.5 capfuls, assuming a standard capful holds about 1 tablespoon. Always ensure to mix well and follow safety guidelines when handling bleach.