Matter and Energy Chapter 3.1

What do you think of when you hear the word… Kinetic

Kinesiology (scientific study of biological movement) Kinesthetic learning (learning by doing/tactile learning/learning by physical movement)

So what does kinetic mean? Motion! So what is the kinetic theory of matter? – Theory of the motion/movement of matter 3 common states of matter: A) Gases B) Liquids C) Solids 4 th state of matter? – Plasma!

3 Main Parts of the Kinetic Theory 1. All matter is made up of atoms and molecules that are always in constant motion

Kinetic Theory… 2. The higher the temperature of the substance, the faster the particle moves

Kinetic Theory 3. At the same temperature, more massive (heavier) particles move slower than less massive (lighter) particles Who would win?

 Diamond Solids—definite volume, definite shape Particles in a solid are in a fixed position (even though they are still moving!—they just vibrate) Structures of solids are rigid – Crystalline Solids—have an orderly arrangements of atoms or molecules Ex: Iron, Diamond, and Ice – Amorphous Solids—composed of atoms and molecules that are in no particular order Ex: Rubber and Wax Rubber 

Liquids—definite volume, not shape Particles of a liquid can slide past each other, so the shape of a liquid changes Particles move faster than in a solid, overcoming the forces of attraction between the particles (allowing particles to flow freely) Liquids take the shape of their container, but the volume does not change!!

Another property of water… Surface tension!—force acting on the particles that cause the particles to stick together on the surface

Gases- no definite volume or shape Particles are free to spread in all directions What would happen if I sprayed perfume at the front of the room? – The gas particles will expand to fit the room, and eventually you will all smell it! Gas changes in volume and in shape! How many balloons can one helium tank fill? 700! Gases change both their shapes and volumes, and once they are under less pressure and in a wider space, they can expand!

Plasma Believe it or not… – Plasma is the most common state of matter!...more than 99% in the universe! Where is plasma found? – Sun, stars, lighting, fire, aurora borealis Plasma does not have a define shape, the particles have broken apart, and they can conduct electric currents! – So, similar to gases except that gases cannot conduct an electric current!

Energy Energy is the ability to change or move matter (to do work) Thermal energy = the total amount of kinetic energy of the particles that make up a substance

Temperature What is temperature? Scientifically, temperature is the measure of the average kinetic energy of the particles in an object Hot temperatures = particles moving faster = greater amount of kinetic energy

Change of State Chemical or Physical Change? – Physical! The identify of a substance does not change, only the amount of energy of a substance If energy is added = particles move faster If energy is removed = particles move slower

Water—Which state has the most energy? Go from solid to liquid by adding heat! Go from liquid to gas (Steam) by adding heat! A transfer of energy (known as heat) leads to a change of state Draw this in notebook 

Changing state with energy Endothermic changes—changes that result from adding heat – Example: A solid changing to liquid by the addition of heat  atoms vibrate faster and break apart from their fixed positions (melt) – Melting point—temperature at which a substance changes from a solid to a liquid – Melting point of water? 0°Celsius

Changes of State Evaporation—change of state from a liquid to a gas (ex: boiling) – Boiling point of water at sea level = 100°Celsius Sublimation—the process by which a solid turns into a gas – Example: Dry ice (solid carbon dioxide) sublimes to form gaseous carbon dioxide

Changes of State Other changes can occur by releasing heat = exothermic reactions Condensation  change of state from a gas to a liquid Water molecules slow down, and a large amount of atoms clump together Freezing  change of state from a liquid to a solid – Water molecules slow down further, and the attraction between particles overcomes their motion

Changing States.. When a substance loses or gains energy, either its temperature changes OR it is changing states (NOT BOTH) When changing states, temperature stays the same If you add heat to ice at 0°C, the temperature will not rise until the ice has melted

Changes of State