An atom of sodium has the electronic configuration 2,8,1 2, 8, 1\,2,8,1 whereas an atom of potassium has the configuration 2,8,8,12, 8, 8, 12,8,8,1. When added to water, potassium reacts much more vigorously than sodium.
Explain, in terms of atomic structure and electronic configurations, why potassium is more reactive than sodium.
75 exam-style questions on Edexcel GCSE Chemistry 7.1 Group 1, covering 7.1.1 Classifying elements by group in the periodic table and 7.1.2 Properties and reactions of the alkali metals. Each one has a worked solution and a mark scheme showing where the marks go.