know that a Brønsted–Lowry acid is a proton donor and a Brønsted–Lowry base is a proton acceptor
know that a Brønsted–Lowry acid is a proton donor and a Brønsted–Lowry base is a proton acceptor
be able to calculate the pH of a weak acid making relevant assumptions
be able to define the ionic product of water, Kw
be able to calculate the pH of a strong base from its concentration, using Kw
be able to define the terms ‘pKa’ and ‘pKw’
be able to analyse data from the following experiments:
i) measuring the pH of a variety of substances, e.g. equimolar solutions of strong and weak acids, strong and weak bases, and salts ii) comparing the pH of a strong acid and a weak acid after dilution 10, 100 and 1000 times
be able to calculate Ka for a weak acid from experimental data given the pH of a solution containing a known mass of acid
be able to draw and interpret titration curves using all combinations of strong and weak monobasic acids and bases
be able to select a suitable indicator, using a titration curve and appropriate data
know what is meant by the term ‘buffer solution’
understand the action of a buffer solution
know that acid-base reactions involve the transfer of protons
be able to calculate the pH of a buffer solution given appropriate data
be able to calculate the concentrations of solutions required to prepare a buffer solution of a given pH
understand how to use a weak acid–strong base titration curve to:
i) demonstrate buffer action ii) determine Ka from the pH at the point where half the acid is neutralised
understand why there is a difference in enthalpy changes of neutralisation values for strong and weak acids
understand the roles of carbonic acid molecules and hydrogencarbonate ions in controlling the pH of blood
be able to identify Brønsted–Lowry conjugate acid-base pairs
be able to define the term ‘pH’
be able to calculate pH from hydrogen ion concentration
be able to calculate the concentration of hydrogen ions, in mol dm-3, in a solution from its pH, using the expression H+ = 10–pH
understand the difference between a strong acid and a weak acid in terms of degree of dissociation
be able to calculate the pH of a strong acid
be able to deduce the expression for the acid dissociation constant, Ka,for a weak acid and carry out relevant calculations
CORE PRACTICAL 9: Finding the Ka value for a weak acid