develops and evaluates questions and hypotheses for scientific investigation CH11/12-1

designs and evaluates investigations in order to obtain primary and secondary data and information CH11/12-2

conducts investigations to collect valid and reliable primary and secondary data and information CH11/12-3

analyses and evaluates primary and secondary data and information CH11/12-5

describes, explains and quantitatively analyses acids and bases using contemporary models CH12-13

Properties of Acids and Bases

IQ1: What is an acid and what is a base?

Students:

● investigate the correct IUPAC nomenclature and properties of common inorganic acids and bases (ACSCH067)

● conduct an investigation to demonstrate the preparation and use of indicators as illustrators of the characteristics and properties of acids and bases and their reversible reactions (ACSCH101)

● predict the products of acid reactions and write balanced equations to represent:

– acids and bases

– acids and carbonates

– acids and metals (ACSCH067)

● investigate applications of neutralisation reactions in everyday life and industrial processes

● conduct a practical investigation to measure the enthalpy of neutralisation (ACSCH093)

● explore the changes in definitions and models of an acid and a base over time to explain the limitations of each model, including but not limited to:

– Arrhenius’ theory

– Brønsted–Lowry theory (ACSCH064, ACSCH067)

Using Bronsted-Lowry Theory

IQ2: What is the role of water in solutions of acids and bases?

Students:

● conduct a practical investigation to measure the pH of a range of acids and bases

● calculate pH, pOH, hydrogen ion concentration ([H+]) and hydroxide ion concentration ([OH–]) for a range of solutions (ACSCH102)

● conduct an investigation to demonstrate the use of pH to indicate the differences between the strength of acids and bases (ACSCH102)

● write ionic equations to represent the dissociation of acids and bases in water, conjugate acid/base pairs in solution and amphiprotic nature of some salts, for example:

– sodium hydrogen carbonate

– potassium dihydrogen phosphate

● construct models and/or animations to communicate the differences between strong, weak, concentrated and dilute acids and bases (ACSCH099)

● calculate the pH of the resultant solution when solutions of acids and/or bases are diluted or mixed

Quantitative Analysis

IQ3: How are solutions of acids and bases analysed?

Students:

● conduct practical investigations to analyse the concentration of an unknown acid or base by titration

● investigate titration curves and conductivity graphs to analyse data to indicate characteristic reaction profiles, for example:

– strong acid/strong base

– strong acid/weak base

– weak acid/strong base (ACSCH080, ACSCH102)

● model neutralisation of strong and weak acids and bases using a variety of media

calculate and apply the dissociation constant (Ka) and pKa (pKa = -log10 (Ka)) to determine the difference between strong and weak acids (ACSCH098)

● explore acid/base analysis techniques that are applied:

– in industries

– by Aboriginal and Torres Strait Islander Peoples

– using digital probes and instruments

● conduct a chemical analysis of a common household substance for its acidity or basicity (ACSCH080) , for example:

– soft drink

– wine

– juice

– medicine

● conduct a practical investigation to prepare a buffer and demonstrate its properties (ACSCH080)

● describe the importance of buffers in natural systems (ACSCH098, ACSCH102)