ICPE Elements of Chemistry

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ICPE Elements of Chemistry

• Adapted from Conceptual Physical Science Hewitt
• By Jim Barnaby 2004

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Matter

• Read page 361small kid talking about carbon
•  Matter
•   Anything with mass and volume
•  Chemistry
•   The study of matter and the transformations it
  can undergo
• Focuses on the study of nonliving things

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Phases of Matter (solid)

• Phases (states) of Matter
• SolidDefinite shape and definite volume
• Solid molecules vibrate about fixed positions,
  but they cannot move past one another.

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Liquid

• LiquidNo definite shape, definite volume
• -Takes the shape of its container
• Liquid molecules move faster and can slip past
  one another.
• (Grains of rice when poured act exactly like
  water molecules)

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Gas

• GasNo definite shape, No definite volume
• -Diffuses to fill all available space (takes the
  shape and volume of its container)
• Demo with H2S morning breeze

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Gas

• Gas particles are in constant motion moving
  greater than 400 m/second (1500 km/hr).
• A single gas particle undergoes 10,000,000,000
  collisions each second
• Fast moving particles are separated by large
  distances.

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Plasma

• PlasmaHigh temperature, high-energy gas
• Cannot be contained by ordinary matter
• Plasma is contained by forces gravity,
  electromagnetic
• Use word document for chart

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Physical Properties

• Physical Properties
• Characteristic that differentiates one type of
  matter from another. Color, odor, 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 tendency of a substance to change chemical
  identity (transforms into a different substance)
• Fe rust (exposed to water and O2)
•  
• Gold has the interesting chemical property of
  resisting a change in identity. So do other
  relatively inert materials such as platinum and
  helium.

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Chemical Change

• 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
• Metals undergoing a chemical change (rxn) are
  reacting

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Chemical Reaction

• 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 (produces heat
  energy), endothermic (absorbs heat energy),
  light, bubbles, burning, explosion (releases
  energy), flammabilityability to burn

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Physical Vs 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.
• Page 367 potassium chromate and ammonium
  dichromate fig 15.9 15.10

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Oxidation

• Physical or chemical change? The fun game show
• Enjoy all class demonstrations
• Oxidation
• Combination of an element with oxygen to produce
  oxidespartial loss of electrons or total loss of
  electrons or a gain of oxygen 

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Rusting

• Rusting
• When elemental iron turns to rust it slowly
  oxidizes to compounds such as iron III oxide
•  4 Fe (s) 3 O2 (g) 2 Fe2O3 (s)
•  Do tubular rust lab
• Does the steel wool gain or lose mass as it rusts?

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Classification of matter

• According to makeup, matter is classified into (4
  classes)
• Mixtures
• Solutions
• Elements
• Compounds

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Mixtures

• Mixture
• 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.

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Heterogeneous Mixture

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

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Homogeneous Mixture

• 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 glass, stainless steel, sugar
  dissolved in water

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Colloids

• 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. Colloids do
  separate on standing as do many heterogeneous
  mixtures.
• Examples milk, whipped cream, toothpaste,
  suntan lotion

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Solution

• Solution
• Type of homogeneous mixture formed when one
  substance is dissolved in another. Best mixed
  of all mixtures. Particles are evenly spread
  out.
• Examples soda pop, lemonade, kool aid,

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Solute/Solvent

• Solute substance that is dissolved (sugar)
• Solvent substance that does the dissolving
  (water)
•  
• Solutions can exist in any of the three phases
  solid, liquid or gas.
• Property of solution is that particles are evenly
  spread out (dissolved)

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Solubility

• 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?

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Increase solubility

• Increase temp-increase solubility
• Decrease temp-decrease solubility
• Increase agitation-increase solubility
•  
• A substance that dissolves in another substance
  is soluble in that substance.
• Insoluble does not dissolve (sand in water)

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Alloys

• Alloys
• Metal solutions, examples of solids dissolved in
  solids.
• Gold jewelry is a solid solution of Au and Cu
• Brass is an alloy of Cu and Zn
• Sterling silver is an alloy of Ag and Cu
• Stainless steel is an alloy Cr and Fe

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Pure Substances

• Pure substances
• Matter that cannot be separated by physical
  means (elements and compounds)

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Element

• Element
• Substance that contains only 1 type of atom
• Examples H, He, O, B anything from periodic
  table

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Compound

• Compound
• Substance formed when different types of atoms
  bond with one another
• Examples NaCl, C12H22O11, NaOH, AgCl,

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Chemical Compounds

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

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Molecule

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

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Elements/Compounds/Mixtures

• Properties of elements, compounds and mixtures
  chart on word document
• Sketch matter flow chart on the board

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Elemental formula

• Elemental formula
• Atomic symbol along with a numerical subscript
  to indicate the number of atoms grouped together
• O2 - 2 - O atoms
• O3 - 3 O atoms
• S8 - 8 S atoms
• 4 O2 - 4 O2 molecules - 8 - O atoms

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Compounds Vs. elements

• 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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Chemical formula

• Demonstrate tower of charcoal in hood
• Chemical Formula
• Denotes the composition of a compound. Atomic
  symbols with subscripts denote ratio of combined
  atoms.
• Examples NaCl, Fe2O3, KCl
•  
• Know naming compounds page 374 (blue box)

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Purified in nature?

• Demo chalk in water
• Demo liquid nitrogen in can
• 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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Instant water?

• Demo instant water
• Impure water can be purified by
• a. removing the impure water molecules
• b. removing everything that is not water
• c. breaking down the water into its simplest
  components
• d. adding some disinfectant such as chlorine
•  Complete study guide
• Prepare for unit test O fun