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MATTER
What it is all about
Chemistry – Matter Unit
• What is matter?
• What is the organization of matter?
• What is the nature of matter?
Mixtures Pure Substances
MATTER
Can the matter be separated by physical means?
Heterogeneous
Homogeneous
Compounds
Elements
Separation by chemical meansConstant composition
Matter
Matter is anything that occupies space and has mass.
The particle theory of matter.
The particle theory states that…
all matter is made from particles
different particles have different properties
particles are constantly in motion
States of Matter
A solid has a definite shape and volume.
A liquid has a definite volume but no definite shape.
A gas has neither a definite volume or shape.
Gas Liquid Solid
SOLIDS
• the attraction between particles is strong so the matter holds its shape. The particles are still moving, but they are not able to slide past each other
LIQUIDS
• the attractive forces are not as strong. The particles
are able to move past each other and slide around
GAS
• the attraction between particles is so weak that they fly in every direction filling the container that they are held
vaporization
condensation
subl
imat
ion
subl
imat
ion
melting
solidification (freezing)
Properties of Matter
Physical Properties:
• a quality of a substance that can be observed or measured without changing the substance’s chemical composition
Examples: color, texture, boiling point, density, mass etc…
Chemical properties
• Properties that do change the chemical nature of matter • Properties the matter exhibits when chemical change occurs
Ex. oxidation, flammability, corrosiveness, pH, reactivity
Physical Properties Subcategories
• Extensive Properties depend upon the amount of matter that is present.
Ex. Length, mass, volume, heat …etc
• Intensive Properties do not depend on the amount of matter present. These properties are the same for a given substance regardless of how much of the substance is present.
Ex. Color, density, melting point, ductility, temp… etc
• Boiling point• Specific gravity (at constant temperature)• Surface tension• Viscosity (at constant pressure and temp.)• Freezing point• Solubility in water (hot/cold)• Density• Melting point• Mass• Volume• Specific heat capacity• Heat • Temperature
Examples of physical properties
Density
• the mass of a substance per a specific amount of volume
Density = mass
volume
• The mass and volume are directly proportional. If one increases the other increases
Physical and chemical change
• Physical change– the altering of the physical form but not
composition of matter– ex. Pounding, pulling, changes of state
• Knowledge of physical change leads to…– the understanding of separation of mixtures
– ex. Distillation, crystallization, chromatography, filtration
Chemical change
• Chemical change– change in which the matter is converted into
matter with different composition and properties
Indicators of chemical change
1. heat and/or light energy– Energy changes within the system
2. Production of gas
- release of gas from the system
3. Formation of a precipitate
- when two (or more) solutions are put together an insoluble solid is produced
4. Color change
- the system changes color
- not always an indicator of chemical change (can be physical
Mixtures Pure Substances
MATTER
Can the matter be separated by physical means?
Heterogeneous
Homogeneous
Compounds
Elements
Separation by chemical meansConstant composition
MIXTURES
mixture: - combination of two or more kinds
of matter each of which retains its own composition and properties
- physical blend of two or more substances
heterogeneous mixture: - a mixture containing substances that are not evenly distributed
- different from point to pointex. granite ---> quartz, feldspar, and mica
More of Mixtures:
Phase
• mixtures that are obviously heterogeneous and have separate, distinct parts
Ex. Oil forming layers in water is another
Interface – the region where two or more phases meet
M o M
homogeneous mixture - a mixture containing substances that are
uniformly distributed with the particles blended completely
- composition and properties are uniform throughout
- also called solutions (mixed on a scale of individual particles) ex. I molar copper II sulfate
• To the eye, the mixture appears to be pure substance.
SolutionsSolutions(Homogeneous Mixtures)(Homogeneous Mixtures)
Can you tell the difference?Can you tell the difference?
Parts of a Solution• SOLUTE – the part of
a solution that is being dissolved (usually the lesser amount)
• SOLVENT – the part of a solution that dissolves the solute (usually the greater amount)
• Solute + Solvent = Solution
Solute Solvent Example
solid solid Brass: Copper and Zinc
solid liquid Seawater: NaCL in water
gas solid Moth balls: naphthalene
liquid liquid Ethyl alcohol and water (miscible)
gas liquid SODA: CO2 gas in water
gas gas AIR: O2 gas, N2 gas
DefinitionsDefinitions
Solutions can be classified as Solutions can be classified as saturatedsaturated or or ununsaturatedsaturated..
A A saturatedsaturated solution contains the solution contains the maximum quantity of solute maximum quantity of solute that dissolves at that that dissolves at that temperature.temperature.
An An unsaturatedunsaturated solution contains solution contains less than the maximum less than the maximum amount of solute that can amount of solute that can dissolve at a particular dissolve at a particular temperaturetemperature
DefinitionsDefinitionsSUPERSATURATED SOLUTIONSSUPERSATURATED SOLUTIONS contain more solute contain more solute
than is possible to be dissolved in a given amount of than is possible to be dissolved in a given amount of solventsolvent
Supersaturated solutions are unstable. Supersaturated solutions are unstable.
-- the supersaturation is only temporary-- the supersaturation is only temporary
-- need to warm the solvent so that it will dissolve -- need to warm the solvent so that it will dissolve moremore
-- then need to cool the solution slowly-- then need to cool the solution slowly
http://www.youtube.com/watch?v=jVhPZg3dxIg http://www.youtube.com/watch?v=HnSg2cl09PI&feature=related
• Some mixtures are in-between heterogeneous mixtures and homogeneous solutions.
Somewhere In Between
• suspension • has clumps that stay floating• filtering a suspension will usually separate the particles.
• colloid • has very small clumps that almost make a solution • the clumps are so small that they pass through most filters
• milk is an example of a colloid.
• emulsion • the clumps of particles are held with an emulsifying agent. • mayonnaise as an example
Define the following wordssolubility.
Miscible
Immiscible
Separation of Mixturestypes of…
• Filtration– Separation of mixture on the basis of
differences in the size of the particles– Mostly used to separate solids from liquids (but
filtration is used to separate all phases of matter from one another)
Ex. Air filters separate gas (air) from solid (dirt particles)
http://www.youtube.com/watch?v=nJVbFIIycKo
• Distillation– Based on the tendency of a substance to
vaporize (turn to a gas)– Based on boiling point differences– The substance in the mixture with the lowest
boiling point will vaporize first from the mixture
Ex. Crude oil http://www.youtube.com/watch?v=26AN1LfbUPc
• Chromatography– Based on the differences in solubility– Two types Gas and Paper– Mixture separates as it travels (most soluble
separates first)
Solute – substance that gets dissolved
Solvent – substance that does the dissolving
Ex. Separating ink in a marker http://www.youtube.com/watch?v=OKxRx0ctrl0&feature=related
http://www.youtube.com/watch?v=LY44uD2miYM
• Crystallization– Separation of the mixture is based on
solubility differences– Temperature changes within the mixtures
change solubility of parts of the mixture
Solubility – the amount of a solute that is able to dissolve in a given amount of solvent
Ex. Rock candy http://www.youtube.com/watch?v=l_USYub3djY&feature=related
Concentration: • amount of solute in a given amount of solvent (can be determined quantitatively)
Dilute: • a solution with a small amount of solute per solvent amount (relative term)
Concentrated: • a solution with a large amount of solute per solvent amount (relative term)
BOTH DILUTE AND CONCENTRATED ARE QUALITATIVE
SOLUTION CHEMISTRY
Concentration of SoluteConcentration of SoluteConcentration of SoluteConcentration of Solute
The amount of solute in a solution is The amount of solute in a solution is
given by its given by its concentrationconcentration.
Molarity (M) = moles soluteliters of solution
The concentration of a solution is said to be its molarity.
Ex. 1 M CuSO4
“1 molar copper II sulfate