Physical vs. chemical changes Everett

Matter—anything that has mass and takes up space. Matter and Chemistry Matter—anything that has mass and takes up space. Chemistry—the study of matter and how it changes.

Properties of matter Examples: Physical Property: a characteristic of a substance that can be observed without changing the substance into another substance. Examples:

Properties of matter Chemical Property: a characteristic of a substance that describes its ability to change into other substances. Examples:

Changes of matter Physical Change: any change that alters the form or appearance of a substance but does not make the substance into another substance. **Change in state or change in size. What are some verbs/action words that describe changing physically but not chemically? List:

Changes of matter Chemical Change: a change in matter that produces one or more new substances. You can’t get the original compound back. The atoms are rearranged to form new substances with different chemical and physical properties. List:

Reactants and products Reactants: the substances that undergo change in a chemical reaction. Products: the new substances formed by the reaction. CO2 + H2O  H2CO3 Different from physical change, because physical is like this: CO2 (s) + Heat  CO2 (g)

Dot Examples 1 Oxygen gas broken down. 2 Magnesium oxide formed.

Precipitate Lead Iodide

Evidence for chemical reactions 1. Formation of a precipitate. 2. Formation of a gas. 3. Change in color. 4. Change in scent. 5. Change in temperature.

Energy changes When bonds break and/or form, energy is involved. Energy can be required or released. Endothermic Reaction: the total making and breaking of bonds results in a net absorption of energy. So, does it become hot or cold?

Energy changes Exothermic Reaction: the total making and breaking of bonds results in a net release of energy. So, does it become hot or cold? Released into nearby matter. Example: Gases released by burning of airplane into atmosphere propel it forward.

Video https://www.youtube.com/watc h?v=BgM3e8YZxuc