In: Chemistry
What difference in the properties of 0.1 M HCl and 0.1 M acetic acid caused the pH's of equal volumes of each to differ?
HCl is a strong acid & acetic acid is weak acid. A strong acid completely dissociate to give ions in solution (100% ) whereas a weak acid only slightly dissociates(1%) in solution.
HCl + H2O <==> H+(aq) + Cl-(aq)
0% 100%
CH3COOH + H2O <==> H+(aq) + CH3COO- (aq)
99% 1%
0.1 M solution of hydrochloric acid has a pH value of 1.00, while a 0.1 M solution of ethanoic acid has a pH value of 2.87.
HCl when react in water fully ionised producing H+ ions.
CH3COOH only partially dissociate into ions, leaving a high percentage of unreacted molecules in the solution.
The concentration of H+ ion in both acid is differ which caused the pH's of equal volumes of each to differ.