Physical Changes in Matter

Physical change- A change in a substance that doesn’t change the identity of the substance.

EX: grinding, cutting, melting, evaporating, dissolving

Includes all changes of state (physical changes of a substance from one state to another)

Chemical Changes in Matter

Chemical Change - change in which a substance is converted into a different substance.

AKA: Chemical reaction

reactants- substances that react

products- substances that form

The identity of the reactants change!

The mass of the substances before and after a chemical or physical change is equal- Law of Conservation of Mass

Signs that a chemical change has occurred

Color change

Light produced

Heat produced

Cold produced

Precipitate produced

Fizzing/bubbling- production of a gas

Burning- something on fire

Rusting

tarnishing

Energy Changes in Matter

Many chemical and physical changes involve energy

Energy can be : light, heat, sound…

Exothermic change- change that gives off energy (feels warm on outside)

Endothermic Change- change that uses up energy (feels cold on outside)

Changes of State

Solid - liquid : energy absorbed

liquid -- gas : energy absorbed

solid --- gas : energy absorbed

Gas -- solid: energy released

Gas- liquid: energy released

Liquid-- solid: energy released

Energy changes when matter changes states

You need this info too

Read pages 7-8- Due: Tomorrow- You can complete this in your NOTES- I will check this off tomorrow!

1. Define: Change of state

2. Define: solid, write a description of the behavior of the atoms

3. Define: liquid, write a description of the behavior of the atoms

4. Define: gas, write a description of the behavior of the atoms

5. Define: plasma, write a description of the behavior of the atoms