WJEC Chemistry for AS Level Student Book: 2nd Edition

What this book contains The contents of this book match the speci cation for WJEC AS Level Chemistry. It provides you with information and practice examination questions that will help you to prepare for the examinations at the end of the year. This book addresses: ▪ The mathematics of chemistry, which will represent a minimum of 20% of your assessment. ▪ Practical work. The assessment of your practical skills and understanding of experimental chemistry represents a minimum of 15%. ▪ The three Assessment Objectives required for the WJEC Chemistry course. ▪ The nature of the examinations. The book content is clearly divided into the units of this course. These are Unit 1 – The Language of Chemistry, Structure of Matter and Simple Reactions, and Unit 2 – Energy, Rate and Chemistry of Carbon Compounds. Each chapter covers one topic. The main text of each topic covers all the points from the speci cation that you need to learn. At the beginning of each chapter is a list of learning objectives highlighting what you need to know and understand and a maths checklist to help you know what maths skills will be required. At the end of each chapter is a set of Test Yourself questions, designed to help you practise for the examinations and to reinforce what you have learned. At the end of each unit, you will nd questions selected from WJEC Eduqas examination papers set over the past few years. Answers to all the questions are given at the end of the book. There is also a Periodic table on page 225. Marginal features The margins of each page hold a variety of features to support your learning: Key terms are terms that you need to know how to de ne. They are highlighted in blue in the body of the text and appear in the Glossary at the back of this book. You will also nd other terms in the text in bold type, which are explained in the text, but have not been de ned in the margin. The use of key terms is an important feature since examination papers may contain a number of terms that need to be de ned. Knowledge check questions are short questions to check your understanding of the subject, allowing you to apply the knowledge that you have acquired. These questions include lling in blanks in a passage, matching terms with phrases speci c to the topic under study, and brief calculations. Answers are provided at the back of the book. As you progress through your studies, study points are provided to help you understand and use the knowledge content. In this feature, factual information may be emphasised, or restated to enhance your understanding. Study point Light is electromagnetic radiation in the range of wavelength corresponding to the visible region of the electromagnetic spectrum. Key terms Atomic orbital is a region in an atom that can hold up to two electrons with opposite spins. 7 Knowledge check (a) Use electrons in boxes to write the electronic con guration of: (i) an atom of phosphorus, P. (ii) a magnesium ion, Mg 2+ . (b) Write the electronic con guration in terms of subshells for a chromium atom. 4 WJEC Chemistry for AS Level