Matter is made up of very small parts called atoms. Atoms can combine in different numbers and in different ways to make different molecules. Atoms and molecules make up all of the different ...

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 ...

Christine Helms does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond ...