In the textbook we stated As a rule of thumb you can conside

In the textbook, we stated, \"As a rule of thumb, you can consider strong acid concentrations between 0.1 M and I x 10 M to be equal to hydronium ion concentrations.\" How is an ideal strong acid different from a real strong acid? What happens to violate the rule when the strong acid concentration is higher than the upper limit of this range? What happens below the lower limit of the range? 2.

Solution

An ideal strong acid HA is one that dissociates completely into H⁺ and A^- ions and the latter that is A^- being strictly unreactive in the solution. However in reality even very strong acid donot show complete dissociation, even though the percentage of undissociated form of the acid might be very low.It is an approximation that we consider real strong acid to dissociate completely.

According to general definition of acid solutions, acidic solutions are ones which have H⁺ ion concentration be between 1 to less than 10^-7.However since acidic solutions are defined in pH terms so acidic solutions are generally defined to be between pH 1-6 that is concentration of H⁺ between 0.1 to 10^-6. Near pH 7 the solution is considered to be neutral and below pH 1 the dissociation of the acid will be relatively less violating the assumption for 100% dissociation of strong acids.

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