Senior Secondary Chemistry is a complete course consisting of a set of three pupils’ textbooks. The authorship comprises university science educators, practising classroom teachers and school administrators. In this Third Edition, the contents of the books have been enlarged to include the requirements of the examination syllabus as approved by the West African Examinations Council. Each book is clearly graded and paced in a way to highlight the in-depth treatment of the contents. The selection of contents into each book is based mainly on the prescribed core curriculum and partly on experiences gathered by the authors in their several years of teaching at the senior secondary school level.