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