Matter:

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Matter

• Its what the worlds made of.

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Chemistry Studies Matter- Branches of Chemistry

• Organic
• Study of most carbon-containing compounds
• Basis for most life processes as well as
  plastics, drugs, petrochemicals, food, etc.
• Inorganic
• Study of non-organic substances
• Physical
• Study of properties and changes of matter and
  their relation to energy
• Analytical- identification of the components and
  composition of materials
• Biochemistry- study of substances and processes
  occurring in living things
• Theoretical- use of math and computers to provide
  theories that explain chemical observations
  predict properties of new compounds

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Chemistry Studies Properties

• Extensive properties
• depend on amount of matter present
• volume, mass, and amount of energy present
• Intensive properties
• independent of the amount present
• boiling point, melting point, density, conducting
  electricity and energy, phase change energy and
  others

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States of Matter

• Solid Definite shape and volume
• Liquid Definite volume but variable shape
• Assumes the shape of its container
• Gas Neither definite shape or volume
• Expands to fill any size container
• Takes the shape of the container
• Plasma Extremely high energy state where
  electrons have been ejected

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Changes of State

• Melting
• Freezing
• Vaporizing
• Boiling- change from liquid to vapor within the
  liquid as well as at the surface
• Evaporation- change from liquid to gas at the
  surface of the liquid occurs at much lower
  temperatures than boiling
• Condensing
• Sublimation- example dry ice (CO2)
• Deposition- example frost forming on a cold
  surface

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What is Matter made of?

• Elements
• Compounds
• Mixtures
• See classification scheme for matter on p.11 of
  the text

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What is Matter made of?

• Elements-cannot be broken down
• Atomic-most elements can exist as individual
  atoms(smallest particle of any element).
  Examples Fe, Au, Ag, Al
• Molecular-some elements are
• Diatomic H2, O2, N2, F2, Cl2, Br2, I2
• Triatomic O3
• Tetratomic P4
• Octatomic S8
• Elements are found on Periodic Table

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What is Matter made of?

• Compounds-Two or more elements chemically bonded
  together
• These can be broken down into smaller compounds
  or elemental parts
• Examples CaCO3(chalk), Fe2O3(rust)
• Smallest particle is a Molecule

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Pure Substances

• Always have a fixed composition
• Can be elements or compounds
• Always have the same properties
• Always have the same composition
• Pure water is always 11.2 Hydrogen and 88.8
  Oxygen by mass

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What is Matter made of?

• Mixtures-These are made of two or more chemicals
  that are not chemically bonded together.
  Examples Sand, Salt/Pepper, Milk, Blood, Muddy
  water
• Homogeneous uniform throughout
• Heterogeneous differences are found
• Mixtures can often be separated easily by
  physical means such as filtration, distillation
  or chromatography.

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Filtration

• Separates solid substances from liquids and
  solutions.
• Coffee Filters
• Some water filters
• Pool filters using sand or DE- diatomaceous earth
  (spongy skeleton)

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Distillation

• Separates
• Homogeneous
• mixtures using
• the differences in
• boiling points.
• BPH20 100C
• BPNaCl 808C
• Water vapor rises first and condenses in the
  tube.

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Chromatography

• Separates substances on the basis of differences
  in solubility in a solvent.

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Classification Flowchart
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Physical Properties

• Observed without changing the identity of a
  substance
• Volume, mass, size, color, shape, smell,
  hardness, density, texture, melting boiling
  points, temperature

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Physical Changes

• Change that alters appearance or form of material
  but does not change the identity of the substance
• Examples tearing paper, breaking pencil, ice
  melting
• Phase changes are ALWAYS Physical Changes

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Chemical Properties

• What are the chemical activities of the material
• Does it react with Oxygen
• Does it react with Water
• Does it react with Chlorine
• Does it react with Fluorine
• Does it react with

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Chemical Changes

• A chemical reaction occurs that produces NEW
  substances
• Old chemicals bonds(Reactants) must be broken and
  new ones(Products) formed usually with energy
  exchanging
• Example burning fuel, digesting food,
  Photosynthesis, rusting iron, plant decay

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2 Kinds of Chemical Reactions

• Exothermic
• Releases heat into surroundings
• Might feel warm or hot to the touch
• Reactants have higher energy in their bonds
• Examples
• Mixing acid with bases
• Burning of a fuel
• Digestion

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2 Kinds of Chemical Reactions

• Endothermic
• Absorbs heat from the surroundings
• Could feel cool to the touch
• Products have more energy than reactants
• Examples
• Cooking an egg
• Dissolving Baking Soda
• Photosynthesis
• Cooking coffee beans

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Chemical Equations

• 2 H2(g) O2(g) ? 2 H2O(l) Energy
• Coefficients
• ? yields
• (s), (g), (l)
• Energy is always involved-Heat or Light
• Exothermic
• Endothermic
• Balancing will follow later
• Matter CANNOT be created or destroyed but it can
  be changed in reactions

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Measuring Matter

• Using Le Système International (SI)(Metric System
  only)(see pg 34)
• Volume -- VLxWxH VPr2h V4/3Pr3
• Mass -- gram, Kilogram- not affected by gravity,
  based on quantity of matter
• Weight -- Pounds, Ounces- caused by the pull of
  gravity which can change
• Volume Gallons, Liters- space that a substance
  takes up
• Density mass/volume

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Measurements are wrong!

• Measurements are not pure numbers
• Measurements are made by man using instruments
  made by man and subject to error
• UNCERTAINTY FACTORS 3452ml
• Every measuring device has an UF
• Usually ½ of the smallest readable graduation

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Uncertainty in Derived Quantities

• For Addition and Subtraction
• Round all numbers to accuracy of the least
• Do the desired math operation (A)
• Add all Uncertainty Factors of each measurement
  used above (B)
• Write as AB

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Uncertainty in Derived Quantities

• Multiplication and Division
• Round all numbers to accuracy of the least
  accurate number involved
• Do the desired math operation
• Divide each uncertainty by its measurement. Pick
  the largest uncertainty from previous step
• Multiply the Answer (C) times the value of B
• B X C new UF
• Combine B D (Derived answer w/ new UF)

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Density

• Physical property of a substance
• Mass
• Density ----------
• Volume

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Density

• Mass/Volume
• Affects the buoyancy of material. Does it float?
• Is NOT affected by size of sample
• Is affected by change in temperature