Physical Science
Everything in the universe can be classified as either matter or energy. Kinetic Energy Theory: All particles of matter are in constant motion.
State of Matter Bose- Einstein Condensate Shape Volume Speed of Par0cles Behaves as a single particle Behaves as a single particle Behaves as a single particle Temperatures Extremely low Solid Definite Definite Slow Low Liquid Not definite Definite Medium Medium Gas Not definite Not definite Fast High Plasma Not definite Not definite Very fast Extremely high
In 1924 (82 years ago), two scientists, Albert Einstein and Satyendra Bose predicted a 5 th state of matter which would occur at very very low temperatures. Einstein Bose +
In a Bose- Einstein condensate, atoms can no longer bounce around as individuals. Instead they must all act in exactly the same way, and you can no longer tell them apart! https://www.youtube.com/watch?v=nagpab4obs8
Solids have a definite shape and volume because the particles vibrate around fixed locations Vibrations are repetitive and back and forth. Particles have a strong attraction to each other.
Particles in liquids are closely packed together so there is an attraction between the particles Not as strong as in solids Liquids take the shape of their container because the particles can flow to new locations The volume is constant because of the attraction between the particles.
Particles are never at rest Average speed is 1600 km/ hr. (994 mph) Atoms or molecules of a gas travel in a straight line until they: 1. strike another particle 2. hit the sides of a container These collisions cause air pressure
Plasma is an ionized gas. A plasma is a very good conductor of electricity and is affected by magnetic fields. Plasma, like gases have an indefinite shape and an indefinite volume. Examples of plasma:
SOLID: molecules vibrate slowly, but don t move LIQUID: molecules slip and slide past each other GAS: molecules spread out and bounce around PLASMA: molecules break apart and the pieces (protons, neutrons, and electrons) float separately
Kinetic Theory of Gases: constant motion of particles in a gas allows the gas to fill a container of any shape or size Particles are in constant random motion. The motion of one particle does not affect the motion of another particle unless they collide. The force of attraction between particles is low because the particles are so far apart.
Definition: A phase change is a reversible physical change that occurs when substances change from one state to another.
FILL IN THE 6 PHASE CHANGES ON THE IMAGE BELOW:
THE TEMPERATURE OF A SUBSTANCE DOES NOT CHANGE DURING A PHASE CHANGE!!!!
liquid to solid energy is released (exothermic) the molecules slow down so they have more of an attraction to each other the arrangement becomes more orderly
solid to liquid energy is gained (endothermic) molecules move more quickly and are able to flow past each other.
liquid to gas (endothermic). There are two types of vaporization: EVAPORATION 1. Evaporation: changes a liquid to a gas below the boiling point Molecules must have enough energy to escape. Occurs at the surface of the liquid. BOILING 2. Boiling: occurs at the boiling point As the particles in the liquid gain energy, they move faster. This causes collisions within the liquid. Molecules can escape when the vapor pressure in the liquid is equal to the atmospheric pressure
Gas to liquid (exothermic) Ex. Morning dew
Solid to gas without going through the liquid phase. (endothermic) Gains enough energy fast enough to skip the liquid phase Ex. Dry ice, moth balls
Gas to solid without going through the liquid phase (exothermic) Loses enough energy fast enough to skip the liquid phase Ex. Frost on windows
Energy is either absorbed or released The words we use to classify phase changes as either gaining or absorbing energy are endothermic and exothermic
Endothermic Energy is absorbed or gained Endothermic phase changes: melting, vaporization, sublimation
Exothermic Energy is released Exothermic phase changes: freezing, condensation, deposition