Final answer:
To prepare a 100 PPM chlorine based sanitizing solution typically involves adding 2 teaspoons of household bleach to 1 gallon of water, depending on the concentration of the bleach being used (option b). It is critical to ensure proper dilution and to follow safety guidelines.
Step-by-step explanation:
To prepare a 100 PPM chlorine based sanitizing solution, one must determine the appropriate concentration of chlorine required and then dilute a chlorine-containing compound, such as bleach, to the desired strength. Given the options provided, an accurate volume or mass must be chosen to achieve a concentration of 100 PPM (parts per million). A common household bleach contains about 5.25% to 8.25% sodium hypochlorite, varying by brand and product. It is important to know the specific concentration of the starting bleach solution to ensure that you're creating the correct dilution for the sanitizing solution.
For the example of disinfecting tap water recommended by the CDC, it is often suggested to use a small amount of household bleach, such as a few drops or up to a teaspoon, diluted into a gallon of water. Considering these guidelines, to achieve a 100 PPM chlorine concentration, adding 2 tablespoons (which is significantly more than what is required for drinking water disinfection) could lead to an excessive concentration that exceeds the 100 PPM target.
Therefore, the correct answer for achieving 100 PPM would be more likely to involve adding a smaller amount, such as option b) Add 2 teaspoons of bleach to 1 gallon of water, depending on the concentration of the starting bleach solution. Always ensure to use an accurate conversion between teaspoons and gallons and follow safety guidelines when handling and diluting chemicals.
Hence, the answer is option b.