By: Mrs. “the long weekend was wonderful” Burge Properties of matter By: Mrs. “the long weekend was wonderful” Burge

Recap! What is the difference between physical properties and chemical properties?? Physical properties are observed without changing the matter Chemical properties are observed and do change the matter Keep in mind that matter is not destroyed it is changed Law of conservation of mass- the mass of all substances that are present before a chemical change (reactants) equals the mass of all the substances that remain after the change (products)

States of matter Gas state- particles are constantly moving Kinetic Theory-explains how the gas particles behave All matter is composed of tiny particles (atoms, molecules and ions) 2. These particles are in constant, random motion 3. These particles collide with each other and with the walls of any container in which they are held 4. The amount of energy that the particles lose from these collisions is negligible (not enough to count)

States of matter Liquid State- particles are still constantly moving but slower with less energy than in the gas state Because they have less energy they cannot overcome the attractive forces between them They can slide by each other (why liquids flow) but they still cling to each other

States of matter Solid State- particles are still constantly moving but even slower with even less energy than in the gas or liquid state The molecules cannot overcome the attraction to each other They still vibrate against each other but they are fixed in a position Crystalline- their particles have specific geometric arrangements

Thermal Energy The thermal energy with in particles is what causes them to vibrate (how much they vibrate depends on what state they are in and how much energy they have) Thermal energy – the total energy of a materials particles (both active or kinetic energy and their potential energy) Energy from the motions of particles from forces that act within or between particles

Temperature Temperature- used to explain how hot or cold something is This is the average kinetic energy of the particles in the object Molecules at 0 degrees Celsius have less kinetic energy than molecules at 100 degrees Celsius

Changing States Melting point- temperature at which a solid becomes a liquid This is caused by the particles gaining more energy Ice cubes in a glass of water melt because the liquid is hitting against the ice particles transferring energy and cause the particles in the ice to move and vibrate more Heat of fusion- energy required to change a substance from solid to liquid at its melting point The opposite of this is freezing- the freezing point is the temperature at which a liquid becomes a solid (these are at the same temperature just depends on the situation)

Changing States Evaporation- Liquid to a gas Occurs at the surface of a liquid when the particles gain enough energy to escape the forces of the liquid Can happen at any temperature Boiling point- liquid is the temperature at which the particles of the liquid have the same pressure of the particles of the external forces pushing on it Heat of vaporization- amount of energy required for the liquid at its boiling point to become a gas

Changing States Condensation- Gas to liquid, gas particles losing energy and the attractive forces cause them to come closer together and slow down back to a liquid state Example: steam going back to water on your hand, condensation on your water glass from the molecules that has evaporated

Changing States Sublimation- the process of a solid changing directly into a gas without forming a liquid Dry ice

Graphing heat curves

Plasma Plasma- matter that has enough energy to overcome not just attractive forces between its particles but within its atoms atoms collide with such power the electrons are completely stripped off of the atom Examples: Stars

Thermal Expansion Thermal Expansion- an increase in the size of a substance when the temperature is increased and a decreased in size when the temperature is decreased Examples; Sidewalks, roads, thermometers

Amorphous-Is Amorphous Solids are solids that do not have a specific melting point and gradually turn into a liquid over time Example: Butter, glass Amorphous Liquid Crystals are liquids that do not lose all of their structure Example: LCD screens