Final answer:
Among the compounds cited, HBr is the strongest acid followed by an assumed alcohol (C SOH), then NH4Cl as a weak acid, while KCl is neutral. The acidity ranking is determined based on the proton donation ability and the acid ionization constant.
Step-by-step explanation:
To rank compounds from most acidic to least acidic, we have to consider the properties that make a substance acidic or basic. Typically, compounds that donate protons (H+) easily are considered acidic, and those accepting protons are basic. The strength of an acid can also be identified by its acid ionization constant (Ka), with larger values indicating stronger acids.
Looking at the given compounds (C SOH, which appears to be a typo but will be ignored, KCl, HBr, NH4Cl), HBr is a strong acid that ionizes completely in water, followed by NH4Cl, which can act as a weak acid since NH4+ can donate an H+. KCl is a salt that results from a strong acid and a strong base, so it's neutral. Without further information, 'C SOH' cannot be accurately placed, but if it represents a generic alcohol (R-OH), then it is typically less acidic than HBr but more acidic than KCl in its molecular form.
Thus, the order from most acidic to least acidic, assuming 'C SOH' is an alcohol, should be:
- HBr
- C SOH
- NH4Cl
- KCl