Chemistry Unit 1: Chapter 3 Matter

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Chemistry Unit 1Chapter 3 Matter
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Chemistry is
Review . . .

• the study of the composition, structure, and
  properties of matter and the changes it undergoes

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Chemicals are

• any substance that has an unchanging
  composition.
• The term material can be substituted

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Matter

• Overview
• I. States/Phases of Matter
• II. Subcategories of matter
• A. Element vs. compound
• B. Pure substances vs. mixture
• C. Heterogeneous vs. homogeneous materials
• III. Changes in Matter
• IV. Solutions Solubility

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I. Four Physical States (Phases) of Matter

• Solid definite volume and shape particles
  packed in fixed positions.
• Liquid definite volume but indefinite shape
  particles close together but not in fixed
  positions
• C. Gas neither definite volume nor definite
  shape particles are at great distances from one
  another
• D. Plasma high temperature, ionized phase of
  matter as found on the sun.
• Volatile easily changes into gas at room
  temperature may sublime or evaporate.

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II. Movement in the Three States
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Copper States - Solid
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Copper States - Liquid
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Copper States Vapor (gas)
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Summary Characteristics of the states
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Ticket out the Door

• 3-2-1
• List 3 states of matter
• List 2 properties of each state
• List 1 question you still have

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II. Classification of Matter (Section 3.1 pages
47-53)
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solvent
mixture
solution
atom
homogeneous
Compound
molecule
pure substance
solute
element
heterogeneous
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Classification of Matter

• A. Pure Substance materials that always have
  the same (definite) composition
• 1. Element simplest forms of matter made up
  of one type of atom (the building block of all
  matter).
• Ex carbon, sodium, helium
• 2. Compound substance that is made from the
  atoms of two or more elements that are chemically
  bonded in a definite ratio. (Molecules
  smallest part of a compound)
• Ex NaCl sodium chloride
• sugar (sucrose) C12H22O11

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• B. Mixture 2 or more different materials
  physically combined
• 1. Homogeneous uniform in composition
  properties throughout
• Ex) salt water, air, antifreeze, alloys,
  carbonated water, etc.
• a.Solution homogeneous mixture consisting of a
  solute a solvent
• i . solute dissolved material
• ii. solvent material doing the dissolving
  (usually water called aqueous)

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• 2. Heterogeneous not uniform in composition
  properties throughout different phases
• Ex sand
• a. Suspension particles are dispersed
  throughout a liquid, but eventually settle out
  (muddy water)

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• b. Colloid tiny particles are dispersed
  throughout another substance, but will not settle
  out (orbitz, jello)
• Aerosols solid or liquid particles in a gas Ex.
  Paint, fog, smoke
• Foams a gas in a liquid
  Ex. whipped cream, marshmallow
• Emulsion a liquid in a liquid
  Ex. mayonnaise. cheese
• Sols solids in liquids or solids in solids Ex.
  jellies, opals
• Tyndall effect
• Brownian motion

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Comparison of Solutions, Colloids Suspensions
 
 
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C. Comparing Mixtures and Compounds

• Mixture ?
• Individual components retain properties
• No definite composition
• Can be separated physically

• Pure substance
• New properties
• Definite composition
• Cannot be separated physically

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1. Separation of a Mixture
The constituents of the mixture retain their
identity and may be separated by physical means.
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Separation of a Mixture

• a. Filtering can separate a mixture such as muddy
  water, or separating a precipitate from the
  remaining solution.

• b. Evaporation can separate a mixture such as
  saltwater

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Separation of a Mixture
c. The components of dyes such as ink may be
separated by paper chromatography.
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Separation of a Mixture
d. Distillation
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2. Separation of a CompoundThe Electrolysis of
water

• Compounds must be separated by chemical means.

• With the application of electricity, water can be
  separated into its elements

Reactant ? Products
Water ? Hydrogen Oxygen
H2O ? H2 O2
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Review Classification of Matter
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III. Changes in Matter (Section 3.2 pages 56-62)
Intro Complete anticipation guide
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Which of the following are physical changes and
which are chemical changes?

• Boiling water
• Iron rusting
• Food spoiling
• Adding pigment to paint
• T/F
• Chemical reaction is another way to say chemical
  change.
• A precipitate forming is a sign of a chemical
  change.
• All color changes are a result of a chemical
  change.

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Physical Change
A. Physical Property
A characteristic of a substance that does not
involve a change in the identity of the substance.
A change that does not change the identity of the
substance.
Example
State Changes
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Chemical Change
B. Chemical Property
A characteristic of a substance that is observed
while interacting with another substance.
A change in which one or more substances are
converted into different substances.
Ex Chlorine reacts w/ Na
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1. Evidence of a Chemical Change

• Formation of a gas
• Formation of a precipitate (ppt) a solid formed
  from two solutions
• Change in energy either temperature or light
• Color change sometimes indicate a chemical change.

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2. Chemical Change Chemical Reaction
(rxn)

• Chemical rxns - process where 2 or more
  substances interact to form a new substance.
• Reactants -
• Products -
• ? (arrow) means yield

Starting substances
Ending substances
C2H5OH 3 O2 ? 2 CO2 3 H2O Energy
Reactants ? Products
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Which of the following are physical changes and
which are chemical changes?

• Boiling water
• Iron rusting
• Food spoiling
• Adding pigment to paint
• T/F
• Chemical reaction is another way to say chemical
  change.
• A precipitate forming is a sign of a chemical
  change.
• All color changes are a result of a chemical
  change.

physical
chemical
chemical
physical
True
True
False
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IV. The Mole
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V. Solution Composition
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• What are the parts of a solution? Give an
  example of each.
• What are some characteristics of a solution?

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Solutions- Review

• Solute substance which is dissolved
• Solvent substance in which the solute is
  dissolved in.
• Characteristics
• 1. A solution is homogeneous if it is well
  stirred during its formation.
• 2. The dissolved particles do not settle out.
• 3. Clear / transparent
• 4. Cannot be filtered to remove particles
• 5. Considered to be a single phase.

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2. Temperature
1. Nature of solvent
HOW MUCH WILL DISSOLVE? Factors Affecting
Solubility
3. Pressure
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Factors Affecting Solubility

• 1. Nature of solvent
• Ex) polarity like dissolves like nonpolar
  solute will dissolve in nonpolar solvents
• Ex) vitamins fat soluble (A,D,E,K) vs water
  (B,C)
• 2. Temperature
• For most solids and liquids ?T, ?solubility
• For gases ?T, ? solubility
• Ex.)thermal pollution dissolved O2 in water
• 3. Pressure gas solutes only ?P, ?solubility
• Ex.) carbonated beverages

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2. Stirring
1.Size of particles
HOW FAST WILL IT DISSOLVE? Factors Affecting
Rate of Solution
3. Amount of solute already dissolved
4. Temperature
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Factors Affecting Rate of Solution

• 1.Size of particles smaller is faster rate
  (surface area increases)
• 2. Stirring increases rate
• 3. Amount of solute already dissolved
  (Concentration) the more you have in (more
  concentrated), the slower the rate
• 4. Temperature
• For most solids and liquids ?T, ? rate
• For gases ?T, ? rate

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Measuring Concentration

• Dilute vs. concentrated
• Dilute relatively small amt of solute
• Concentrated - relatively large amt of solute
• Mathematical expressions
• A.    Mass percent mass of solute x 100
• mass of solution
• B. Molarity moles of solute
• L of solution
• C. Molality moles solute
• kg solvent

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Ex Calculate the molarity of a solution that
has 58 grams of NaCl dissolved in 0.5 L of
solution?

• M mol / L
• Convert grams to mole
• Find the molarity.
• You can do this in one factor label problem if
  you wish.

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Calculate the molarity of a solution that has 250
grams of KBr dissolved in 2 L of solution?
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How many grams of solute are dissolved in a 2 L
of 0.1 M Na2SO4 solution?

• M mol/L
• 1. Find the moles of solute
• 2. Convert to grams
• You can do this in one factor label problem if
  you wish.

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Solution Equilibrium

• Process of dissolving (dissociation)
• Initially- many particles leave surface of
  crystal
• Some dissolved particles start to return to
  crystal surface
• Eventually, the number of
  particles leaving the
  crystal surface number
  returning to the surface
  SOLUTION EQUILIBRIUM

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Solubility Saturation

• Saturated at solution equilibrium the
  solution is holding as much solute as it can at a
  given temp. (the relationship btw the amount of
  solute able to be dissolved and the temp is
  called the solubility of the substance.)
• Unsaturated solution contains less than the
  max. amount of solute for that temperature.
• Supersaturated the solution contains more
  solute than a saturated solution can normally
  hold very unstable.

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Solubility Curve
The line indicates the solubility of the
substance. saturated solution Where on the
graph would represent a supersaturated
solution? unsaturated solution?