Open an introductory chemistry textbook. What is a covalent bond? A covalent bond occurs when atoms share electrons in a molecule. What is a hydrogen bond? A hydrogen bond is an electrostatic ...

Try these interactive flashcards based on GCSE chemistry past papers. By working your way through the flashcards created by experts, you can prepare for your chemistry exams and make your revision ...

Most organic chemical compounds contain loops of six carbon atoms called benzene rings. The nineteenth-century German chemist August Kekulé claimed to have pictured the ring structure of benzene after ...