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Matter
Chapter Chapter 2.12.1
MatterAnything that has mass Anything that has mass and occupies space.and occupies space.ChemistryChemistry is the study is the study of matter and how it of matter and how it changes.changes.
PLEASE KEEP YOUR HANDS IN THE BOAT AND PLEASE DON”TFEED THE ANIMALS.
Pure Substances
Uniform and definite Uniform and definite compositioncompositionCanCan’’t be separated physically t be separated physically only chemicallyonly chemically2 types Elements & compounds2 types Elements & compounds
Pure Substance
ElementsElements –– a substance that cannot a substance that cannot be broken down into smaller be broken down into smaller substances.substances.AtomsAtoms –– smallest particle that has smallest particle that has properties of an element. properties of an element. Both expressed by symbolsBoth expressed by symbols
Compounds
CompoundsCompounds –– a substance a substance formed when two or more formed when two or more elements elements chemicallychemically combine combine together.together.
Molecules
The smallest unit of a The smallest unit of a substance that exhibits all of substance that exhibits all of the properties characteristic the properties characteristic of that substanceof that substance..Two or more atoms chemically Two or more atoms chemically combinedcombined
Chemical Formulas
Ex. CEx. C1616HH1010NN22OO22
MixturesA physical combination of more than one substance.(Two Types)
Homogeneous Mixtures
SolutionsSame throughout (miscible)
ex: flat soda, salt water, carbonated drinks
Heterogeneous Mixtures
Not uniformly mixed (immiscible)Substances that need to be shaken
ex: noodle soup, granite
Classifying Liquid Mixtures:
miscible-dissolve into each otherimmiscible-don’t mix into each other. You can see layers
ex: oil and water.
Matter and Energy
2.2
Kinetic Theory
1.All matter is made of atoms and molecules that act like tiny particles.
Kinetic Theory
2.These tiny particles are always in motion. The higher the temperature, the faster the particles move.
Kinetic Theory
3. At the same temperature, heavier particles move slower than lighter particles.
Phases/States of Matter
GasGasliquidliquidsolidsolidplasmaplasma
States of Matter - Gases
no definite shape.no definite volume.easy to compress.most random arrangement of particles.Most spread out.
Gases
Property of gases is called pressure.–the force exerted per unit area of a surface
Liquids
Definite volumeno definite shape
(takes shape of container)Difficult to compressdisorderly arrangement on particlesClose together
Liquids
Property of Liquids is called viscosity.–the resistance of a fluid to flow
Solids
Definite shapeDefinite volumeDifficult to compressOrderly arrangement of particles close togetherSmallest amount of movement of particles.
Energy
The ability to change state or move matter.Changing state does not change composition of the substance
liquid gassolid
Changes of State
Law of conservation of matter
Matter cannot be created or destroyed.It only changes its state or rearranges its atoms.
Law of conservation of energy
Energy cannot be created or destroyed.It converts from one form to another during chemical or physical changes.
Properties of Matter
2.3
Physical PropertyA characteristic of a substance that can be observed or measured without changing the composition of the substance.
Physical PropertyMelting and freezing points.Solubility–Dissolving of a solid into a liquid.
Density
Densitymass/volume (D=m/V)UNITS:mass – (g)Volume – (mL) or (cm3)density – (g/mL) or (g/cm3)
DensityBuoyancy-
The force with which a more dense fluid pushes a less dense substance upward.
ex. floating ice.
Chemical Properties
The way a substance reacts with others to form new substances with different properties.
Chemical Properties
FlamabilityReactivitycorrosion
Physical ChangesA change in the physical form or properties of a substance that occurs without a change in composition.
Chemical ChangeA change that occurs when a substance changes composition by forming one or more new substances.
Chemical Change4 signs:Evolution heat or lightColor changeFormation of gasFormation of a precipitate (solid residue)
