Calcium reacts with oxygen to form calcium oxide, CaO. Calcium oxide is used to reduce the acidity of soil.
An atom of calcium can be represented as 2040Ca\mathrm{^{40}_{20}Ca}2040Ca. Oxygen has atomic number 8.
Give the electronic configuration of a calcium atom.
Explain, in terms of electrons, how calcium atoms and oxygen atoms form calcium oxide.
Give the electronic configuration of an oxide ion.
Compare the numbers of protons, neutrons and electrons in a calcium atom and in a calcium ion.
Write an equation, using e−\mathrm{e^{-}}e− to represent an electron, to show the formation of a calcium ion from a calcium atom.
56 exam-style questions on Edexcel GCSE Chemistry 2.3 Ionic bonding, covering 2.3.1 Ions and the formation of ionic bonds, 2.3.2 Naming and deducing formulae of ionic compounds, and 2.3.3 Giant ionic lattices. Each one has a worked solution and a mark scheme showing where the marks go.