Part A - Is HCl a Strong Acid Hydrochloric acid (HCl) is considered a strong aci
ID: 955854 • Letter: P
Question
Part A - Is HCl a Strong Acid
Hydrochloric acid (HCl) is considered a strong acid. For many problems, it is convenient to assume that it completely dissociates to H+ ions and Cl ions. But how good is this assumption? As a way to find out, calculate the relative error that results when one makes this assumption with a 0.1 M solution of HCl. Report your answer as a percent to one significant figure, and include the proper sign. Recall that relative error (in this context) is as follows: Er = ((xi – xt)/xt) × 100; where xi is the value under the assumption that complete dissociation occurs and xt is the true or actual value obtained when the pKa of the acid is taken into account. The pKa of hydrochloric acid is 7. For this problem, you can ignore the contribution of H+ ions due to the autoproteolysis of water. You may want to do this calculation with the aid of a spreadsheet so that you can adjust the format of the cells to retain several figures beyond the decimal point.
Explanation / Answer
HCl is a strong acid It is having complete dissociation. It will be determined by calculating pH of the solution, Because of water leveling effect the concentration of HCl and H3O+ is same. The less pKa value also indicates that the its a strong acid. To calculate the percent dissociation, the amount of change occur required. But that change is very less so its ignorable compare with initial concentration.