The 4 most common <u>States of matter </u>are solids, liquids, gases and plasmas. The <u>States of matter</u> are also called the phases of matter.
2. For a given pure substance, the amount of thermal <u>energy</u> is what separates the different states of matter. The solid state has the least thermal <u>energy</u>. The liquid state has more thermal <u>energy</u> than the solid state. The gaseous state has more thermal <u>energy</u> than the liquid state. And the plasma state has the highest thermal <u>energy</u> of the 4 states of matter.
3. Changing from one state of matter to another is called a <u>phase change</u>. Solids can <u>phase change</u> to liquids or gasses. Liquids can <u>phase change</u> to solids or gasses. Gasses can <u>phase change</u> to liquids or solids.
4. Frost forms from water vapor depositing as ice crystal without first becoming liquid water. This is called <u>Deposition</u>. <u>Deposition</u> is also used in industry to put a thin layer of aluminum on mylar for helium balloons and for potato chip bags.
5. Put wet laundry outside on a clothes line in freezing weather and it will dry. The process is called <u>Sublimation</u> and a solid phase changes to a gas without first melting into a liquid. Dry ice (frozen CO2) undergoes <u>Sublimation</u> and becomes CO2 gas. It skips the liquid state and because we see something that looks like normal ice disappear without making a puddle, we call it dry ice.
6. <u>Vaporization</u> is when a liquid becomes a gas. It can happen slowly at cool temperatures and this is called evaporation. Or it can happen faster at the boiling temperature of the liquid and this is called boiling.
7. In the summer time, I love a glass filled with ice water. But water vapor in the air undergoes <u>Condensation</u> and becomes liquid water on the outside of the glass. Fog and clouds are also formed by <u>Condensation</u> of atmospheric water (water vapor) condensing into liquid water drops.
8. Thermic refers to thermal energy, usually perceived as heat or temperature. Endo refers to “inside.” <u>Endothermic</u> means heat is moving INTO a process and is stored in the products of that process. Heating up liquid water is <u>Endothermic</u> because heat is being put into the process of raising the water temperature and is stored in the kinetic motion of the water molecules. Melting ice into liquid water is <u>Endothermic</u> because heat is being used to break most of the attractive bonds between water molecules so that the molecules are still close to each other, but can slide around each other.
9. Thermic refers to thermal energy, usually perceived as heat or temperature. Exo refers to “outside” like exiting a room to the outside. <u>Exothermic</u> means heat moving out of a process. The heat energy comes from energy stored as kinetic motion of the molecules and broken bonds of attraction. When liquid water cools down, heat comes out of the water and goes to the environment around the water. This is <u>Exothermic</u>. Liquid water undergoing the phase change to become solid water (ice) is <u>Exothermic</u>. The thermal energy absorbed to “melt” the ice is released as the ice freezes.
10. The <u>Kinetic Theory of Matter</u> theorizes that all matter is made of tiny particles (atoms and molecules) that are in constant motion. The amount of motion is an indication of the temperature. At absolute zero, all kinetic motion stops.
