Grade 10 Chemistry

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Grade 10 Chemistry
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What is Chemistry?

• The science that deals with the composition and
  properties of substances and various elementary
  forms of matter
• http//dictionary.reference.com/browse/chemistry
• The study of structure and composition

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What is Chemistry?

• Overlaps with biology and physics
• Examples
• Biochemistry
• Physical Science (What we study)
• Quantum Mechanics

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Branches of Chemistry

• Physical Chemistry (What we study)
• deals with the investigation of the laws and
  theories of all branches of chemistry.
• primary goal is the investigation of the
  structure andtransformation of matter and the
  interrelationships of energy and matter. The
  subject of matter, the experimental techniques,
  and the instruments used are common to
  bothchemistry and physics.

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Branches of Chemistry

• Analytical Chemistry
• is concerned with the separation, identification,
  and composition of all kinds of matter.
  Analytical procedures are used in every branch of
  chemistry.
• Two broad classifications of analytical chemistry
  are qualitative analysis and quantitative
  analysis.
• Qualitative analysis involves the separation and
  identification of the individual components of
  materials. It answers the question, What is
  present?
• Quantitative analysis is, in addition, concerned
  with how much of each component is present.

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Branches of Chemistry

• Organic Chemistry
• is the study of carbon-containing materials that
  are compounds.
• The term organic was derived from the original
  belief that these types of compounds were found
  only in living organisms.
• This branch of chemistry now deals with commonly
  used synthetic substances such as plastics,
  drugs, dyes, explosives, and detergents.
• There are many more organic compounds known that
  those of all the other kinds combined

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Branches of Chemistry

• Inorganic Chemistry
• covers the chemistry of all of the elements and
  their compounds with the exception of carbon and
  its compounds.
• This area of chemistry comprises the
  investigation of those substances which are not
  organic such as nonliving matter and minerals
  found in the earths crust.

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Branches of Chemistry

• Biochemistry
• branch of chemistry which includes the study of
  the materials and processes that occur in living
  organisms.
• These materials are largely organic
  (carbon)compounds.

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Branches of Chemistry

• Nuclear Chemistry
• deals with the changes in the nuclei of atoms and
  the uses of these changes, especially in the
  study of how substances react.
• Radioactive nuclei, both natural and man-made
  decompose spontaneously.

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Matter and Properties (Ch. 4)

• Matter anything that has mass and occupies
  volume
• Ex. Water is matter, oxygen is matter, because
  they all have mass and occupy space. Energy
  (light, heat) is not matter.
• Matter can be classified, from general to
  specific.

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Matter and Properties (Ch. 4)

• Physical Properties
• Properties which define a substance using the 5
  senses
• Ex. Color, lustre, malleability, conductivity,
  magnetism, solubility, melting point, freezing
  point, density, etc.
• Some physical properties can be used to define a
  substance. These are called Characteristic
  Properties.
• Characteristic Properties properties that
  define a substance and separate that substance
  from all others that look the same.
• Boiling Point
• Melting Point
• Density

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Matter and Properties (Ch. 4)

• Chemical Properties
• Properties that define the chemical make up of a
  substance and how it will react with other
  substances.
• Ex. Flammability, reactivity to water, etc.

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Matter and Properties (Ch. 4)

• Make a list of descriptive terms for observations
  of physical and chemical properties.
• Read pages 63-65. Define
• Mass
• Substance
• Atom
• Element
• Compound
• Molecule

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Matter and Properties (Ch. 4)

• Read pages 74 77
• What happens in a change of phase?
• Differentiate between a physical change and a
  chemical change.

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Structure of the Atom and the Periodic Table (Ch.
6)

• The periodic table was classified by Dmitri
  Mendeleev in 1869. He classified elements by
  mass, color, taste, etc
• The Modern Periodic Table is ordered by Atomic
  Number.
• The reason is the numbers are related to the
  structure of the atom. The differing structures
  mean different elements react differently, and
  can be logically classified this way.

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Structure of the Atom and the Periodic Table (Ch.
6)
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Structure of the Atom and the Periodic Table (Ch.
6)

• Finding protons, neutrons and electrons (p.
  109 and p. 131-132)
• Proton
• Electron
• Neutron

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Structure of the Atom and the Periodic Table (Ch.
6)

• To find electrons, it is the atomic number (Z).
  Since atoms are neutral (same number of positive
  and negative charges), the number of protons for
  a neutral atom is the same as the electrons.
• Since neutrons are found in the nucleus, and make
  up the atomic mass, the number of neutrons is the
  atomic mass (A) (rounded to the nearest whole
  number) subtracting the atomic number. (Z)

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Structure of the Atom and the Periodic Table (Ch.
6)

• Why does the atomic mass have a decimal?
• It is the average atomic mass. It is made up of
  all the known isotopes for that element.
• Isotope
• atoms of an element that are identical in terms
  of their chemical properties (numbers of p and
  e-) (Z) but differ by number of neutrons, and the
  Atomic Number (A) differs
• Mass Spectrometry (Read handout)

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Structure of the Atom and the Periodic Table (Ch.
6)

• Finding Average Atomic Mass (p. 138 139)
• The atomic mass of the elements have decimal
  points. This is due to the calculating of the
  average atomic mass, using the percentages of the
  abundance found of each isotope.
• Ex.
• What is the average atomic mass of the element
  oxygen, if the naturally occurring abundance of
  each is 16O (99.759), 17O (0.037) and 18O
  (0.204)?

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Structure of the Atom and the Periodic Table (Ch.
6)

• History of the Atom and Atomic Theory
• Using your electronic device and textbook,
  research the following scientists discoveries and
  theories. Pay special attention to how the
  theory changes over time.
• Keep in mind the difference between a hypothesis,
  theory and a law.

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Structure of the Atom and the Periodic Table (Ch.
6)

• Democritis
• Antoine Lavoisier
• Law of Conservation of Mass
• Law of Definite Proportions
• Law of Multiple Proportions
• John Dalton and Atomic Theory
• JJ Thomson
• Ernest Rutherford
• Robert Millikan
• Neils Bohr

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Structure of the Atom and the Periodic Table (Ch.
6)

• p.121 What were the short comings of
  Rutherfords Model?
• Bohrs Model explained some of the short comings
  of the planetary model and also, how the
  electrons are arranged.

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New Approach to the Atom (Ch. 6 p. 122 - 131)

• Electromagnetic Spectrum
• Line spectra
• Wave vs. Particle
• Bohr Model
• Quantum Mechanical Model

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New Approach to the Atom (Ch. 6 p. 122 - 131)

• Electromagnetic Spectrum
• Entry Level Knowledge
• Grade 8 Electromagnetic Radiation
• How do we see different colors?

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New Approach to the Atom (Ch. 6 p. 122 - 131)

• See light based upon the wavelengths of light
  travelling to our eye.
• How we see color, is our eyes detect the
  wavelength of light that corresponds to that
  color
• Example If we see green all colors are
  absorbed, and green light wavelength is reflected
  back to our eye

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New Approach to the Atom (Ch. 6 p. 122 - 131)

• Emission Spectrum

• Absorption Spectrum

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New Approach to the Atom (Ch. 6 p. 122 - 131)

• Electromagnetic Spectrum
• Wavelength is made of three parts
• Frequency
• Number of wave cycles to pass a given point per
  unit of time (cycles per second or Hertz (Hz))
• Wavelength
• The distance between crests or troughs of a wave
• Amplitude
• The waves height from 0 to crest

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New Approach to the Atom (Ch. 6 p. 122 - 131)
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New Approach to the Atom (Ch. 6 p. 122 - 131)

• There is an inverse relationship between
  wavelength and frequency
• All light moves at the speed of light
• c 3.00 x 10 8 m/s
• Energy is a product of the frequency and the
  speed of light
• Therefore, the greater the frequency, the smaller
  the wavelength and the more energy produced

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New Approach to the Atom (Ch. 6 p. 122 - 131)

• Neils Bohr
• Found when an atom was excited light was given
  off
• Electron gains E, moves from its ground state, to
  a higher E level, and then drops back to its
  ground state, losing E in the form of light
• Light corresponded to the energy given
• Greater the energy, greater the jump, smaller the
  wavelength
• 7 different colors of light, 7 energy levels

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New Approach to the Atom (Ch. 6 p. 122 - 131)
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New Approach to the Atom (Ch. 6 p. 122 - 131)
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Applications of Line Spectrum

• Research one of the following
• Aurora borealis
• Fireworks
• Neon Lights

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Applications of Line Spectrum
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Energy (Ch. 5)

• The essence of chemical reactions is the making
  of a new substance, through a chemical process.
• This means that new bonds are formed by the
  rearranging of old bonds to make a new substance
• All chemical reactions are based upon energy. If
  there is enough energy, the reaction goes if
  not, the reaction does not occur.

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Energy (Ch. 5)

• 95 of all reactions will go to completion
  (REACTANTS to PRODUCTS)
• These reactions are considered SPONTANEOUS
  REACTIONS
• Where does the energy come from?
• Internal
• Bonds between reactants
• When bonds break, E is given off
• If there is enough E, the reaction takes place
• External
• Outside source, like a burner, sun (uv light),
  etc.

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Energy (Ch. 5)

• In a change of state
• When a substance melts, E is ____________.
• When a substance condenses, E is
• _________.
• Animation

Added
Removed
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Energy (Ch. 5)

• Definitions
• Energy
• Work

The ability to do work
Done on an object, in response to a force, moves
some distance
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Energy (Ch. 5)

• Forms of Energy (unit Joule (J))
• Potential Energy
• Stored energy, that is available for doing work
• Kinetic Energy
• The energy moving particles or objects have
• Examples

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Energy (Ch. 5)

• Read p. 90 in your textbook
• How is energy converted from one form to another?
• How is energy converted to do work?
• What is the law of conservation of Energy?

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Energy and Chemical Reactions (Ch. 5)

• How can we tell a chemical reaction has taken
  place?

Precipitate forms
Gas is given off
Color Change
An odour appears
A change in temperature
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Energy and Chemical Reactions (Ch. 5)

• In reactions, a temperature change is a measure
  of energy being lost or gained for the reaction
  to occur
• When energy is lost to the environment, the
  energy of the reactants is greater than the
  products. The surroundings will be warmer.
• This is called an exothermic reaction.
• (Exo out)

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Energy and Chemical Reactions (Ch. 5)

• When energy is gained from the environment, the
  energy of the reactants is less than the
  products. The surroundings will be cooler.
• This is called an endothermic reaction.
• (Endo in)

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Energy and Chemical Reactions (Ch. 5)

• The minimum starting energy to get a reaction
  going is called the Activation Energy.
• It is like going over a fence. You have the
  energy to get over, but need a little extra to
  get over. Once you are on the top, you simple go
  to the other side.
• On the graphs, it is represented by the
  transition from reactants to products.

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Heat Energy, Temperature, and Calorimetry (p. 92
99)

• Temperature is a measure of heat energy
• We use two scales
• Celsius
• Freezing Point of Water 0oC
• Boiling Point of Water 100oC
• Kelvin
• Absolute Zero 0 K (all movement of particles
  stops)
• Freezing Point of Water 273 K

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Heat Energy, Temperature, and Calorimetry (p. 92
99)

• Heat
• Energy transferred from one medium to another in
  a thermal interaction
• Temperature is the measure of heat
• Calorie was used as a unit, but a joule is used
• What is a calorie we find on the food we buy?

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Heat Energy, Temperature, and Calorimetry (p. 92
99)

• Calorimetry
• The measurement of the amount of heat released or
  absorbed in a chemical reaction
• Explain how calorimeter works in your own words.

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Heat Energy, Temperature, and Calorimetry (p. 92
99)

• Calorimetry is a combination of the mass of the
  water, the change in the temperature and a
  constant for the substance called the specific
  heat.
• Specific Heat
• Amount of heat energy needed to raise the
  temperature of 1 unit of mass of the substance,
  by 1 unit of temperature.

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Heat Energy, Temperature, and Calorimetry (p. 92
99)
Substance Specific Heat Capacity at 25oC in J/goC
H2 gas 14.267
He gas 5.300
H2O(l) 4.184
lithium 3.56
ethyl alcohol 2.460
ethylene glycol 2.200
ice _at_ 0oC 2.010
steam _at_ 100oC 2.010
vegetable oil 2.000
sodium 1.23
air 1.020
magnesium 1.020
aluminum 0.900