chemistry chapter 3 properties and classification of matter chemistry- matter and change glencoe...
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ChemistryChapter 3
Properties and Classification of Matter
Chemistry-Matter and ChangeGlencoe
Last revision Fall 2007
MatterMatter – anything that has mass and volume.
Mass – the amount of material that makes an object
Volume – the amount of space an object takes
Light from a lighthouse?
The pen/pencil you are writing with?
Your textbooks? Your
thoughts?
Heat from a fire?
All matter is made of tiny little particles called atoms.
There are 90 There are 90 different different
naturally existing naturally existing atoms and 25 atoms and 25
man made ones.man made ones.
They can all They can all be found be found
on the on the periodic periodic table.table.
2 hydrogen atoms & 1
oxygen atom
1 sodium atom & 1 chlorine
atom
Everything about you and everything around you is made of these atoms or combinations or mixtures of these atoms..
Salt (NaCl)
For example:
Water (H2O)
Properties of Matter
Physical Property - a quality or condition of matter that can be observed or measured without changing the arrangement of atoms that make it
Examples:• color• size• shape• state of matter• texture
These properties can usually be observed using our senses or measured with equipment in the lab.
•Mass•Length•Volume•Boiling point•Melting point
Chemical Properties – property that can only be observed when the arrangement of particles that make the matter are altered
These properties usually tell you how a substance will react in the presence of a second substance.
Examples:Iron reacts with oxygen to form rust.
Metals react with acids to form hydrogen gas.
Changes in Matter
Physical Changes – changes in matter that do not alter the arrangement of atoms that make the matter
Changes in size, shape, and STATE OF MATTER.
Examples:crumpling up a piece of paper
breaking a stick in halfmelting ice
salt dissolving in water
Chemical Changes - changes in matter that DO alter the arrangement of atoms that make the matter
Because you can’t see the particles to determine if arrangement has changes, you can look for clues that tell you a chemical change has occurred.
Clues of a Chemical Change:
Identify the following as either a physical property or a chemical property.
Property Physical Chemical
a shirt is red
sodium is so soft it can be cut with a knife
potassium reacts vigorously with water
paper is flammable
water boils at 100 oC
Identify the following as either a physical change or a chemical change.
Change Physical Chemical
burning toast
breaking a glass
melting butter
leaves changing color
fireworks exploding
Intensive vs. Extensive
Intensive properties are properties unique to a pure substance. It is a property that can be used to identify it.
Ex: Extensive properties are properties
that many kinds of substances can have and will not identify the substance.
Now that we can describe matter, we can begin to classify it
Matter-anything with mass and volumeMatter is separated into two categories:
pure substances and mixtures.Matter
Pure Substance – a substance made of the same kind of atoms or compounds having a unique set of chemical and physical properties
The two categories of pure substances are elements and compounds
Pure Substance
Element simplest type of pure substance made of only 1 kind of atom
Examples:
all particles are identical cannot be separated by a physical
or a chemical change
Compounds made of two or more different kind of
elements chemically combined together in a specific ratio
Examples:
elements in a compound can only be broken apart by a chemical change
Classify the following as either an element or a compound.
Mixtures physical blend of two or more pure
substances. can be separated by a physical
change
The two categories of mixtures are homogeneous and heterogeneous.
Mixtures
Homogeneous Mixtures mixtures that are uniform in composition on
the atomic level. all parts of the mixture have the same
concentration of matter. Different parts of the mixture can not be
identified (transparent appearance for solutions)
Alloys: solution of metal also called a solutionExamples:Salt water, vinegarLemonade, alcohol3% H2O2 and H2O solution
Steel, solder or 14 K gold
Heterogeneous Mixtures mixtures that are not uniform in
composition all parts of the mixture are not the
same the different parts can usually be
easily identified from one anotherExamples:
rocks and sandsalt and pepper
oil and water
Classify the following as either a homogeneous mixture or a
heterogeneous mixture.
Classify the following everyday common objects as a homogeneous mixture or a heterogeneous mixture.
Jelly Pizza
Soda
Lotion Chunky Peanut Butter
Mixed Nuts
Matter
Pure Substances Mixtures
Element Compound Homogeneous Heterogeneous
State of Matter- Matter can be solid, liquid, gas or plasma depending on how much kinetic
energy (or motion) they have.
Solid: Particles vibrate in place. It has a definite volume and a definite shape.
Liquid: Particles roll around each other. It has a definite volume but no definite shape.
Gas: Particles move around colliding with one another. It has no definite volume or shape.
Plasma: Particles are so hot and excited that the electrons leave the nucleus and matter is ionized or charged
Matter in Motion
The Kinetic Molecular Theory states that atoms and molecules are always in motion.
Remember, the temperature of a substance is the measure of its kinetic energy.
That energy can only do one thing at a time:
1.Change the state of the substance.
2.Increase the temperature of a substance.
Depositing
Sublimating
Boiling
Condensing
Melting
1. Changes in the states of Matter
2. Heating Curve
This curve can also work in reverse if energy is being taken away.
Absolute Zero
is the temperature at which all motion of particles stops.
Scientists have yet to reach it.
Separating Mixtures
Mixtures are physical blends of two or more pure substances.
Since they are mixed physically, they can be separated into the individual pure substances by physical changes.
Contrast Compare Contrast
Compare and Contrast the two types of mixtures..
Methods of Separating Mixtures using:
Distillation - method of separating components of a solution using their boiling points.
• involves 3 stages and both are state of matter changes
(1) The solution is boiled to vaporize one component of the solution with the lower boiling point.
(2) As soon as the temperature starts to rise, the vapor stops being collected since this rise in temperature indicates the end of a phase change.
(3) The vapor is cooled to turn it back into a liquid
Freezing and Boiling Points
Example: Separate alcohol and water
1. Dissolve substance that is soluble in water.
2. Filtration - uses a filter of porous material to separate a mixture of liquid and insoluble components
3. Evaporate the liquid portion of a solution which changes to a gas or vapor leaving a solid behind
Solubility
Example: Separate sand and salt.
Magnetism - used to separate components of a mixture when one is attracted to a magnet and one is not
Chromatography - method of separation used to see what colors make up an ink or substance containing different molecules.
Steps of Chromatography1. Material to be separated
is spotted on chromatography paper
2. Paper is dipped into a solution that will be
absorbed by the paper and moves up
3. Some colors move more than others and separate