Do not copy any notes in light green lettering!
Physical Change Change in size, shape or physical state that does not change actual substance
Chemical Change One or more substances change into new substances with different chemical properties VC – Comparing Physical and Chemical Changes
Energy The capacity to do work. All change (physical or chemical) in matter involves energy.
Kinetic Energy – energy due to motion; depends on mass and velocity Potential Energy – energy due to position or condition VC – Kinetic Energy Potential Energy
Law of Conservation of Energy Energy… cannot be created or destroyed. can be transferred from one object to another. Can change form (heat,light,electrical, chemical…). Total amount of energy in the universe never changes. VC – Law of Conservation of Energy
Heat – energy transferred between substances because of their difference in temperature Heat always travels from hot substances to cold A substance feels hot when your hand absorbs energy from it A substance feels cold when your hand loses energy to it VC - Heat
Temperature – measure of the average kinetic energy of the particles of a substance Fahrenheit o F Celsius = Kelvin o C Kelvin – 273 = Celsius K
Specific Heat – amount of energy needed to raise the temperature of 1 g of a substance by 1 o C Unique for every substance Explanation: sunny day at the beach! VC – Specific Heat Capacity
Endothermic Process – when a substance absorbs energy from its environment Ice melting (physical change) cooking food (chemical change)
Exothermic Process – when a substance releases energy into its environment Water freezing (physical change) Wood burning (chemical change)
Which is endothermic, which is exothermic process?
Scientific Method
The Steps 1. Observe 2. Question 3. Hypothesize 4. Test hypothesis (experiment) 5. Analyze results 6. Draw Conclusions 7. If conclusion supports Hypothesis, share information with other scientists
Theory An attempt to explain WHY something happens Based on multiple observations and experiments Can change over time as new observations or experiments are made
Law Explains WHAT happens Based on multiple observations and experimental results Doesn’t change VC – Comparing Theories and Laws
Models A way of showing an object, process, or idea to make it easier to understand Models are simpler than the object, process, or idea they represent
Accuracy v. Precision Turn to page 55