1. NGSS Mixtures and Compounds
Physical and Chemical Changes

2. A mixture is made up of two or more substances.
Each substance in a mixture keeps its individual properties. Also, the parts of a mixture are not combined in a set ratio.
Homogenous Mixtures are evenly mixed mixtures that you cannot see the different parts. Example solutions.
Heterogeneous Mixtures you can see the different parts

3. When two atoms combine they form a chemical bond.
Molecule Group of two or more atoms held together by chemical bonds.
When elements are chemically combined, they form compounds having properties that are different from those of the uncombined elements.

4. Physical Change is any change that changes the form or appearance of matter. The substance will still be the same substance after the change. Example breaking a pencil
Chemical Change Is a change in matter that produces one or more new substances. Example burning sugar.
Law of Conservation of Matter states that matter cannot be created or destroyed in a chemical or physical change.