DATE: Wednesday 29 April 2020 4pm (1hr)
CODE: 7712


This webinar is relevant to all specifications in England and Wales. It will give your students opportunities to consolidate their understanding of how to approach equilibrium calculations, giving them confidence to answer unstructured questions set in unfamiliar contexts. We begin by constructing expressions for Kc and working out relevant units before offering exemplar approaches to using information in questions to calculate required values. A similar approach is followed for calculations involving Kp.

The session will involve active participation, with several activities designed for paired or individual work, using an interactive set of notes which students will be able to refer to after the webinar to improve their exam revision.


  • Revisit and revise how to deduce expressions for Kc and Kp, including relevant units
  • Gain confidence in calculating values for equilibrium constants using a ‘step-by-step’ approach
  • Find routes through extended calculations set in unfamiliar contexts
  • Understand how to organise data presented in questions using the technique ‘What do I know? What can I work out? What am I being asked?’


  • All students of A level Chemistry


4.00 pm – Introduction, welcome and sound check

4.05 pm – Expressions for Kc

  • Activity to gain confidence in writing expressions for Kc and determining correct units
  • Boost confidence ahead of the examinations
  • Give students the opportunity to receive guidance from experts on Expressions for K
  • A step-by-step approach to calculating Kc and equilibrium yield
  • Students work through two calculations using a step-by-step scaffold

4.30 pm – What do I know? What can I work out? What am I being asked?

  • Using data in questions to tackle an extended calculation: what is the examiner looking for
  • Review exemplar questions and answers – finding out how to improve exam skills
  • Find out what the examiner is expecting to see from a top grade answer

4.45 pm – Calculating Kp

  • Consolidating understanding of how to calculate quantities present at equilibrium

Chris Conoley

Chris is a highly experienced teacher of Chemistry, Head of Science and latterly a College Principal. He is the author of numerous educational textbooks, including the much praised Collins Advanced Science Chemistry, now in its third edition. As a Senior A Level Examiner, he understands how important it is that students acquire and develop the science skills necessary for success. He leads training courses for teachers both in the UK and overseas and is passionate about making science relevant, accessible and fun.