The three states of matter can be represented by the particle model. This model explains the properties of substances in their different states, as well as changes of state. Changes of state: ...

The latest short science news items from C&EN. 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 ...

Note: This video is designed to help the teacher better understand the lesson and is NOT intended to be shown to students. It includes observations and conclusions that students are meant to make on ...