Some students assert that the numerical value of pH must always lie between and for…
CHEMISTRY · Multi-part · A Level · Chemistry · Acids and bases · Acids and bases
Problem
Some students assert that the numerical value of pH must always lie between 0 and 14 for aqueous solutions at 25∘C. A teacher prepares a set of hydrochloric acid solutions with molarities ranging from 1.0×10−4M to 3.0M in order to challenge that claim.
(a) Describe how the concepts of acid strength and acid concentration each influence the hydronium-ion concentration in solution.
(b) Without performing a detailed logarithmic calculation, justify whether the pH of the 3.0M hydrochloric acid solution is expected to be negative. Base your reasoning on order-of-magnitude arguments.
(c) Explain why the conventional 0–14 range for pH values does not represent a fundamental chemical limit for aqueous solutions at 25∘C.