Physical-Chemical%20Properties%20Mixtures/Elements/Compounds

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Physical-Chemical Properties Mixtures/Elements/Com
pounds

• SNC1D

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Matter

• Anything with mass and volume

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Atoms

• Smallest particle of an element that has all the
  physical and chemical properties of that element
• Basic building block of all matter
• Atoms are mostly empty space

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Molecule

• 2 or more atoms bonded together.
• Smallest particle of a compound that has all the
  properties of that compound.
• Examples H2O NaCl Cl2

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Compounds

• Substance formed when two or more different types
  of atoms bond with one another
• Composed of 2 or more atoms bonded together
• Examples NaCl, C12H22O11, NaOH, AgCl

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Compounds differ

• Chemical compounds are uniquely different from
  the elements that make them up.
• Sodium and chlorine are extremely toxic by
  themselves, however sodium chloride is necessary
  for good health.

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The Particle Theory of Matter

• All matter is made of tiny particles that have
  empty spaces between them.
• Different substances are made up of different
  kinds of particles.
• Particles are in constant random motion.
• The particles of a substance move faster as its
  temperature increases.
• Particles attract each other.

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Classification of matter

• Matter is classified into 4 classes
• Matter exists as
• Mixtures
• Solutions
• Elements
• Compounds

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Mixture

• Matter that consists of two or more substances
  mixed together but not chemically combined.
• The substances keep their separate identities and
  most of their own properties, however their
  chemical composition does not change.
• 2 types of mixtures are heterogeneous and
  homogeneous mixtures

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Heterogeneous Mixture

• mixture which does not appear to be the same
  throughout. Parts are easy to recognize and
  separate.
• Examples granite, tacos, bowl of cereal,
  Italian salad dressing, concrete, crunchy peanut
  butter, .

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Homogeneous Mixture

• Well-mixed, appears to be the same throughout.
  Particles are small, not easily recognizable and
  do not settle when the mixture is allowed to
  stand.
• Examples air, milk, glass, stainless steel,
  kool aid

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Colloids

• Homogeneous mixtures where the particles are
  mixed together but not dissolved. The particles
  in a colloid are relatively large in size and are
  kept permanently suspended.
• Examples milk, whipped cream, toothpaste,
  suntan lotion
• Suspensions separate on standing. Colloids tend
  not to separate.
• Example of suspensions ketchup, mustard
• What about milk when it spoils?

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Solution

• Type of homogeneous mixture formed when one
  substance is dissolved in another. Best mixed
  of all mixtures. Particles are evenly spread
  out.
• Examples coffee, lemonade, kool aid, tea
• Solute substance that is dissolved
• Solvent substance that does the dissolving

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Properties of solutions

• Solutions can exist in any of the three phases
  solid, liquid or gas.
• Property of solution is that particles are evenly
  spread out (dissolved)
• Solutions can change their states in the
  following ways
• Sublimation from solid phase to gas phase
• Deposition from gas phase to solid phase
• Freezing from liquid phase to solid phase
• Evaporation from liquid phase to gas phase
• Melting from solid phase to liquid phase

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Solubility

• Amount of solute that can be completely dissolved
  in a given amount of solvent at a specific
  temperature.
• How can you increase the solubility of a
  substance?
• Increase temp-increase solubility (add heat
  energy)
• Increase agitation-increase solubility
• Decrease temp-decrease solubility

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Soluble/Insoluble

• A substance that dissolves in another substance
  is soluble in that substance.
• (sugar is soluble in water)
• Insoluble does not dissolve (sand in water)

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Alloys

• Alloys
• Metal solutions
• Solids dissolved in solids.
• Gold jewelry is a solid solution of Gold (Au) and
  Copper (Cu) and Silver (Ag)
• Brass is an alloy of Copper (Cu) and Zinc (Zn)
• Sterling silver is an alloy of Silver (Ag) and
  Copper (Cu)
• Stainless steel is an alloy of Chromium (Cr) and
  Iron (Fe)
• Bronze is an alloy of copper (Cu) and tin (Sn)

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Pure Substances

• Pure substances
• Matter that cannot be separated by physical means
  (elements and compounds)
•  Element
• Substance that contains only 1 type of atom
• Examples Au, He, O, B anything from periodic
  table

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Elements, compounds, mixtures

• See handout document for chart

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Separate mixtures

• Explain how you could use physical properties to
  separate the following mixtures
• Sand-salt
• Oil-water
• Salt-water
• Rubbing alcohol-water
• Sawdust-sand
• Gold-sand
• Iron filings-sulfur

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Physical Properties

• Physical Properties
• Physical Properties describe objects (matter) and
  are used to identify and compare different types
  of matter
• Colour, odour, size, shape, state (phase),
  texture, hardness, taste, density, boiling point,
  melting point, freezing point, magnetism,
  conductivity, conducts heat, mass, weight,
  volume, solubility

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Physical Change

• Physical Change
• Change in size, state or shape or changes in
  other physical properties. One or more physical
  attributes transform, but the chemical identity
  is unchanged.

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Chemical Properties

• Chemical Properties
• The properties that describe how a substance
  changes into other new substances.
• The tendency of a substance to change chemical
  identity (transforms into a different substance)

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Chemical property-change

• A Chemical Property describes a substances
  ability to change into a different substance, a
  Chemical Change is the process by which the
  substance changes.
•  
• (Example, the ability of a substance to burn is a
  chemical property, the process of burning is a
  chemical change)

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Chemical Reaction

• Chemical Change (Chemical Reaction)
• New substances with different properties are
  formed
• A substance changes its chemical identity, atoms
  are re-arranged to produce a new substance with
  different properties
•  Chemical Reaction
• New substance is formed by the re-arrangement of
  atoms

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Evidence of Chemical Change

• Evidence of chemical change
• Color change, rust, exothermic (hot-produces
  heat energy), endothermic (cold-absorbs heat
  energy), light, bubbles, burning, explosion
  (releases energy), flammabilityability to burn

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Physical or Chemical Change?

• The main difference between a physical and a
  chemical change is that a chemical change
  involves the production of a new substance.
  Physical changes are easily reversed.

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Physical or Chemical

• Physical or Chemical change
• Light a match
• Slice a cake into 4 pieces
• Ice cream melts into mush
• Alka-seltzer in water
• Crumple a piece of Al foil
• Baking soda and vinegar

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Physical or Chemical

• Water freezes into ice
• Water boils
• Jeans fade in the sun
• Bleach clothes
• Digest food
• A candle melts
•  List physical properties for clock, table,
  person, ..etc

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DemosLabs

• Demonstrations
•  Roast marshmallowsC12H22O11 draw rxn on the
  board
• Complete and turn in metal salts flame lab
• Investigate aquarium experiment
• Deep rock jug

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Grocery Store

• How is a grocery store (supermarket) set up?
• Produce, meats, dairy, frozen foods, drinks, etc
•  Imagine how hard it would be to find items if
  there were no organized way of groceries in a
  grocery store.
• Frozen pizza next to panty hose

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Chemical Symbol

• Chemical Symbol
• Shorthand way to represent an element
• Single letter or first letter is always
  capitalized
• Second letter is always lower case
• As, Fe, Se, He, Ar, .

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Chemical Formula

• Elemental (Chemical) formula
• Combination of chemical symbols to represent a
  substances identity
• Atomic symbol along with a numerical subscript to
  indicate the number of atoms grouped together

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Chemical formulas

• O2 - 2 - O atoms
• O3 - 3 O atoms
• S8 - 8 S atoms
• 4 O2 - 4 O2 molecules - 8 O atoms
• NaCl, Fe2O3, KCl

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Applied Chemical Formulas

• List the element and the number of atoms for each
  element
• NaHCO3
• C12H22O11
• 3 H2SO4
• 5 CaCO3

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Remember

• Rememberchemical compounds are uniquely
  different from the elements from which they are
  made.
• Na - toxic explosive in water
• Cl- - toxic green gas, death in less than
  1.5 seconds
• NaCl table saltsodium chlorideessential for
  good health

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The real world

• In nature, it is rare that elements or compounds
  are found in a purified state. We find them
  mixed together in mixtures, which can be
  separated by differences in physical properties.

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Chemical Equation

• Chemical Equation
• Description of a chemical reaction using symbols
  and formulas
•  
• 2 H2 O2 2 H2O
• Draw molecules on board

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Chemical Reaction

• Chemical Reaction
• Atoms are re-arranged and a new substance with
  different properties is formed
• Reactants Products
• Yield, produce

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Chemical reaction

• Existing bonds are broken, atoms are re-arranged,
  new bonds are formed to produce new substances
•  
• Energy is either absorbed or released

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Exothermic Reaction

• Exothermic chemical reaction (HOT)
• Exo out of thermic heat
•  
• Heat energy is released

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Endothermic Reaction

• Endothermic chemical reaction (COLD)
• Endo into thermic heat
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• Heat energy is absorbed
• (Need to add heat energy to keep reaction going)

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Catalyst

• Catalyst
• Speeds up a chemical reaction without being
  permanently being changed itself

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Law of Conservation of mass

• Law of Conservation of Mass (Matter)
• Matter is neither created or destroyed in a
  chemical reaction. Atoms are re-arranged,
  however, the same atoms and number of atoms
  remain on both sides of the reaction.