Volumetric analysis(acid/base) exercises (2006 VCE)


The hydrogen carbonate ion (HCO3-) can act both as an acid and as a base.
i. Write a chemical equation that shows HCO3- acting as an acid when it reacts with water.
Solution


ii. Write a chemical equation that shows HCO3-
– acting as a base when it reacts with water.
Solution.


Hypochlorous acid (HOCl) is a weak acid with an acidity constant, Ka, of 3.0 × 10–-8 M at 25°C. Calculate the pH of a 0.50 M solution of hypochlorous acid at that temperature.
Solution


The hydrogen ion concentration of a solution is described by the term pH. The hydroxide ion (OH-–) concentration is described in the same way by the term pOH.
A solution has a pOH of 3 at 25°C.
i. Calculate the hydroxide ion concentration of the solution, in mol/L
Solution.


ii. Calculate the hydrogen ion concentration of the solution, in mol/L–
Solution.