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Matter Classification, Chemical and Physical Changes, Chemical and Physical Properties, States of Matter, Phase Changes, Heating Curve
Atom
The basic building blocks of matter
Element
Cannot be broken down through chemical reactions (ex. Ne, Cu, Pb, Sn)
Monoatomic: Single atom
Diatomic: 7 elements exist in nature as 2 atoms chemically bonded together (H2, N2, O2, F2, Cl2, Br2, I2)
Molecule
Pure substance with atoms of 2 or more same or different nonmetal elements chemically combined
Compounds
Pure substance made of 2 or more elements chemically combined (ex. H2O, FeS2)
Properties change when you chemically combine elements
Homogeneous Mixtures
Mixtures that contain pure substances that appear uniform and evenly mixed (ex. air, brass, steel, bronze)
Also known as Solution
Heterogeneous Mixtures
Mixture combining pure substances having non-uniform distribution or unevenly mixed
Parts of the mixture can be easily seen and separated
Also known as colloids or suspension
Suspension: you have to stir something to be evenly mixed
Chemistry
The study of the composition, structure, transformation of matter
Physical change
No change in chemical composition
Same substance
Tend to be reversible
ex. blending, mixing, bending, sculpting, shredding, tearing boiling, evaporating, melting, sublimation, deposition
Solid
Not easily compressed → particles have limited free space
Rigid structure → does not flow easily
Fixed shape and volume
Tightly packed together
Vibrating in a fixed position
Least kinetic energy
Liquid
Not easily compressed → particles have limited free space
Flows easily → particles can move past one another
Assumes shape of the part of the container it occupies
Fixed volume, no define shape
Gas
Compressible → lots of free space between particles
Flows easily → moving rapidly and freely
Assumes the shape and volume of the container
Most kinetic energy
Close Circuit
Matter can not move freely
Energy can move freely
Isolated Circuit
Matter can not move freely
Energy can not move freely
Open Circuit
Matter can move freely
Energy can move freely
Endothermic
Requires energy (heat)
Heat is being added
Object will feel hotter than surrounding environment
Exothermic
Heat is being removed/released
Object will feel colder than surrounding environment
Heating/Cooling Curve
Shows what is happening to the Kinetic Energy of molecules
As temperature increases, kinetic energy increases
As temperature decreases, kinetic energy decreases
Energy added during a phase change is being used to overcome intermolecular forces of attraction
Chemical change
Chemical composition changes
New substance is formed
Tend to be “one-way” (irreversible)
ex. 2H2 + O2 → 2H2O2
Burning, cooking, rusting, corrosion, oxidation, tarnishing, decomposition, spoiling, rotting, decaying
Indicators of chemical change/reaction
Energy change → loss/gain of heat
Light produced
New gas (bubbles form)
Solid precipitate is produced
New substance is formed
Color change
Exothermic changes/reactions
Releases energy (can be in the form of heat or light)
ex. fireworks, glow sticks, fireflies
Endothermic changes/reactions
Environment or surrounding feels colder
Take in heat for reaction
ex. photosynthesis
Extensive physical property
Depends on the amount of substance (will change depending on the amount of the substance)
ex. mass, volume, shape, length
Intensive physical property
Will not change depending on the amount of the substance
ex. color, boiling point, melting point, density, conductivity, specific heat, malleability, ductility, luster, opacity, viscosity, attraction to magnets
Melting/Fusion
Phase change from solid to liquid
Gains kinetic energy
Vaporization/Evaporation
Phase change from liquid to gas
Gains kinetic energy
Condensation
Phase change from gas to liquid
Loses kinetic energy
Freezing
Phase change from liquid to solid
Loses kinetic energy
Sublimation
Phase change from solid to gas
Gains kinetic energy
Deposition
Phase change from gas to solid
Loses kinetic energy
STP
Standard Temperature and Pressure
Note 
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