Final answer:
Solutions ranked from most acidic to least acidic: H2SO4, NH4NO3, NaCl, NaCN, and NaOH. H2SO4 is the strongest acid, and NaOH is the strongest base with NaCl being neutral.
Step-by-step explanation:
To rank the given solutions from most acidic to least acidic (and conversely from most basic to least basic), one must understand the properties of acids and bases. An acid is a substance that increases the concentration of hydrogen ions (H+) when dissolved in water, while a base decreases the concentration of H+ by producing hydroxide ions (OH-). The provided solutions can be classified based on known acidic or basic properties and their respective strong or weak nature.
To elaborate on the explanations, H2SO4 is a strong acid that completely dissociates in water, yielding a high concentration of H+ ions. NH4NO3 is a salt that can act as an acidic solution because NH4+ can release H+ ions. NaCl, being the salt of a strong acid and base, dissociates into Na+ and Cl- without affecting the pH. NaCN is salt of a weak acid and strong base, which makes it a weak base in solution. Lastly, NaOH is a strong base that fully dissociates into Na+ and OH-, which greatly increases the pH of the solution.