LESSON OBJECTIVE: Understand entropy as a measure of the disorder of a system. Learning Outcomes: (taken from the Cambridge International AS and A Level Chemistry curriculum) 23.3 Entropy change, ΔS define the term entropy, S, as the number of possible arrangements of the particles and their energy in a given system

In this lesson we focus on the electron and how it arranges itself around the nucleus in principal quantum levels, subshells and atomic orbitals. This is lesson five in our physical chemistry series for Unit 2: Atomic Structure (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). LESSON OBJECTIVE: Understand how the electron exists in principal quantum levels and subshells, to describe the relative energies of the s, p and d orbitals and to sketch the s and p orbitals. LEARNING OUTCOMES (from the Cambridge AS Chemistry Curriculum 2019-2021): 2.3 Electrons: energy levels, atomic orbitals, ionisation energy, electron affinity a) describe the number and relative energies of the s, p and d orbitals for the principal quantum numbers 1, 2 and 3 and also the 4s and 4p orbitals b) describe and sketch the shapes of s and p orbitals