Endothall salt forms mapping: which statement is correct?

• A. Aquathol K is a dipotassium salt and Hydrothol 191 is a monoamine salt
• B. Aquathol K is a monoamine salt and Hydrothol 191 is a dipotassium salt
• C. Both are granular formulations
• D. Endothall does not have salt forms

Answer: (A)

Endothall is used in waters as salts formed with different counterions to adjust solubility and handling. The product names reveal the salt form: Aquathol K is the dipotassium salt of endothall, meaning two potassium ions are paired with the endothall anion. Hydrothol 191 is the monoamine salt, formed with a single amine cation. This is why the correct statement is that Aquathol K is a dipotassium salt and Hydrothol 191 is a monoamine salt. The other options don’t fit because they misstate the salt forms or properties (endothall does have salt forms; these products are not both granular solely by nature, and the salt forms are not swapped).