Chemical systems may be open or closed. They include physical changes and chemical reactions that can result in observable changes to a system. Students study the effects of changes in temperature, concentration of chemicals and pressure on equilibrium systems, and consider that these can be predicted by applying Le Chatelier’s principle. Students also analyse the quantitative relationship between products and reactants in equilibrium reactions to determine an equilibrium constant. From this calculation, they predict the equilibrium position, either favouring the formation of products or reactants in a chemical reaction.
This module also allows students to understand that scientific knowledge enables scientists to offer valid explanations and make reliable predictions. Students make reliable predictions by comparing equilibrium calculations and equilibrium constants to determine whether a combination of two solutions will result in the formation of a precipitate.
In this module, students focus on processing data to determine patterns and trends that enable them to solve problems and communicate scientific understanding of ideas about equilibrium reactions. Students should be provided with opportunities to engage with all the Working Scientifically skills throughout the course.
Inquiry question: What happens when chemical reactions do not go through to completion?
Students:
conduct practical investigations to analyse the reversibility of chemical reactions, for example:
model static and dynamic equilibrium and analyse the differences between open and closed systems (ACSCH079, ACSCH091)
analyse examples of non-equilibrium systems in terms of the effect of entropy and enthalpy, for example:
investigate the relationship between collision theory and reaction rate in order to analyse chemical equilibrium reactions (ACSCH070, ACSCH094)
Inquiry question: What factors affect equilibrium and how?
Students: