2-Changes in Matter: Chemical

    Chemical Changes: When a new substance with different properties from the starting mater is created, a chemical change has occurred. Some examples of chemical changes are rusted steel, cooked eggs and burning wood. The molecules have been re-arranged and then joined together, like when the molecules in the air join up with the fire released carbon molecules. The new compound is carbon dioxide gas, with properties that are different from wood and oxygen (see below). You can sometimes tell if a chemical change has occurred if a new color has appeared, if heat or light energy is given off, if the change is difficult to reverse/seperate, and/or if bubbles of gas are produced. Even if one or more of the things listed above occur, it may simply be a physical change. Below is an image collage of what happens when wood burns.

Oxygen Atom-  Carbon (Wood) Atom-   Carbon Dioxide Molecule (Bonded Oxygen and Carbon)

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