States of Matter and Phase Changes

Solid Definite Shape Definite Volume Particles are fixed in position (They vibrate) Least energy (Slowest moving particles) Particles are closest together

Liquid Indefinite Shape (Takes shape of container) Definite Volume Particles are close together but have enough energy to slide past each other Intermediate energy (Particles move faster than in a solid)

Gas Indefinite Shape (Takes shape of container) Indefinite Volume (Particles fill the entire container) Particles are constantly moving Lots of energy (Particles move faster than those in liquids)

Plasma Super hot and gas-like Can conduct electricity (made of negatively and positively charged particles) Most common state in Universe (stars contain lots of plasma) Most energetic (fastest moving particles) Found in Lightning, Fire, Auroras, Gas Lights

THINK!! What are the 4 different states of matter and how do they differ with respect to shape and volume??

Terms to Know Endothermic Exothermic Process that absorbs energy (heat) from the surroundings Feels cold Exothermic Process that releases energy (heat) to the surroundings Feels warm

THINK!! What is the difference between an endothermic process and an exothermic process?

Changes in States Gases and Liquids Liquids and Solids Vaporization = liquid to gas = endothermic Condensation = gas to liquid = exothermic Liquids and Solids Melting = solid to liquid = endothermic Freezing = liquid to solid = exothermic Gases and Solids Sublimation = solid to gas = endothermic Deposition = gas to solid = exothermic Plasma and Gases Ionization = gas to plasma = endothermic Deionization = plasma to gas = exothermic

Phase Change Graph Used to show energy and temperature needed to change the phase of a specific substance Slanted lines go with a single phase Solid, liquid, or gas Horizontal lines go with a phase change (two phases are present at the same time like having a glass of ice water) Freezing, melting, etc. Temperature doesn’t change during a phase change.

Phase Change Graphs and Energy Changes --Slanted lines indicate a change in temperature, therefore Kinetic Energy (Ek) is changing (increasing or decreasing). --Horizontal lines indicate no change in temperature, so Ek remains constant. However, energy is still being added or removed so from the system. Therefore, Potential Energy (Ep) must be changing (decreasing if a cooling graph where heat is removed, increasing if a heating graph where heat is added).

Why doesn’t the temperature change during that time? THINK!! How many states of matter are present for a horizontal line on a phase change graph? ______ Why doesn’t the temperature change during that time? How many states of matter are present for a slanted line on a phase change graph? _______

Exit Ticket Questions 13 - 16

13. Which state of matter has a definite volume, but not shape? A. solid B. liquid C. gas D. plasma

14. The particles in a solid move ___. A. slower than particles in a liquid B. faster than particles in a liquid C. the same speed as particles in a liquid D. at the speed of light

15. The process of a liquid becoming a gas is called ___. A. condensation B. freezing C. vaporization D. melting

16. In order for a substance to go from a gas to a liquid, heat energy must be ___. A. Added (absorbed) B. Subtracted (released) C. kept the same D. none of the above