Do now

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Do now
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing

• Please take 2 minutes to answer these
• If we cant see atoms, how do we know they exist?
• What are atoms?

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Objectives
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing

• By the end of today, you will be able to
• Content
• Compare the different ways (theories) of
  understanding atoms (matter)
• Language
• Describe the steps (people) that were required to
  figure out the current understanding of atoms.

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Together

• http//www.bbc.co.uk/schools/gcsebitesize/science/
  add_aqa_pre_2011/atomic/atomstrucact.shtml
• After the video clip, make sure you ask me at
  least 1 good question!!!
• Sample project from student

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History of Atomic Theory

• Introduction in the past!

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What are atoms?
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing

• Atoms are
• Just how small are they?
• 1 cm3 of air 45 000 000 000 000 000 000 atoms

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Why do we care so much about atoms?
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing

• ATOMS MAKE UP ALL MATTER!
• So the more we can understand atoms, what they
  look like, and how they behave, the more we can
  understand the world around us.

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Key question

• Who were the first people to think about the atom
  (this is a trick question really think about
  it)?

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Part One

• Democritus A Philosophy of Atoms

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First Atomic Theory
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing

• Think that it was fancy scientists with fancy
  equipment that discovered atoms?
• WRONG!
• Some of the first people to think about atoms
  were actually early Greeks!

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Early Greek Philosophers

• Democritus

• Everything is made of small, indivisible, atoms.
• Not just matter space and time too!!!
• Atoms never change, but they combine to make
  different substances.
• Different atoms have different shapes, sizes, and
  temperatures.

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Properties of Atoms
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing

• Small, pointy atoms ? Solids
• Large, round atoms ? Liquids
• Sharp Atoms ? Bitter Taste
• Round Atoms ? Sweet Taste

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Key question

• What was wrong with the Greek view of the atoms?

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Part 2

• The Science of Atoms

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Antoine Lavoisier
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing

• French chemist, 1700s.
• Executed during the French Revolution!
• One of the first people to quantitatively study
  chemistry!
• Didnt do a whole lot of work investigating
  atoms, but he set the path for scientifically
  studying chemistry.

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John Dalton
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing

• English Chemist and Physicist, 1800s.
• Humble, independent, awkward.
• First scientific atomic theory.
• 1808 A New System of Chemical Philosophy
• Work on colorblindness (Daltonism)
• Welcomed into the Royal Society
• 40 000 in funeral procession

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Daltons Model of the Atom Nothing New?
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing
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Playing with Gas

• Dalton became famous by mixing gases and taking
  down observations
• Lots and lots of observations!
• Dalton took over
• 200 000 observations of gases reacting with each
  other.

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Daltons Experiment
Oxygen
Water
Hydrogen
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Daltons Experiment
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing
Carbon
Carburetted Hydrogen
Hydrogen
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Daltons Experiment
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing
Hydrogen
Ammonium
Nitrogen
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Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing
Oxygen
Nitrous Gas
Nitrous Acid
Oxygen
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What does it all mean?
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing

• Why does not water admit its bulk of every kind
  of gas alike? This question I have duly
  considered, and though I am not able to satisfy
  myself completely I am nearly persuaded that the
  circumstance depends on the weight and number of
  the ultimate particles of the several gases.
• Absorption of Gases, 1805

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Daltons Atomism

1. All matter is composed of extremely small
   particles called atoms.
2. All atoms of a given element are identical,
   having the same size, mass, and chemical
   properties. Atoms of a specific element are
   different from those of any other element.
3. Atoms cannot be created, divided into smaller
   particles, or destroyed.
4. Different atoms combine in simple whole-number
   ratios to form compounds.
5. In a chemical reaction, atoms are separated,
   combined, or rearranged.

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Daltons Atomism (true/false)

• All matter is composed of extremely small
  particles called atoms.

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Daltons Atomism (true/false)

• 2. All atoms of a given element are identical,
  having the same size, mass, and chemical
  properties. Atoms of a specific element are
  different from those of any other element.

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Daltons Atomism (true/false)
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing

• 3. Atoms cannot be created, divided into smaller
  particles, or destroyed.
• We may as well attempt to introduce a new
  planet into the solar system or annihilate one in
  existence, as to create or destroy a particle of
  hydrogen.

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Daltons Atomism (true/false)
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing

• 4. Different atoms combine in simple whole-number
  ratios to form compounds.
• Atoms mix together to make molecules. Can only
  mix whole numbers of atoms.
• All of Daltons gas experiments helped him
  figure out what elements different molecules were
  made of.

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Daltons Atomism (true/false)

• 5. In a chemical reaction, atoms are separated,
  combined, or rearranged.

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Did everyone believe Dalton?
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing

• No!
• Many scientists didnt believe in atomism.
• Ernst Mach famous physicist
• Thought that since you cant actually watch and
  observe atoms, that Daltons theory was
  unscientific.

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NECAP Q
Agenda Do Now Objectives Intro to Atoms Science
of atoms Parts of the atom Redesigning the
Atom Closing
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Which model demonstrates the Law of Conservation
of Matter?
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With a partner

• One of you please talk how the Greeks understood
  the atom
• The other person, please discuss how Dalton
  understood the atom
• Between the two of you, please discuss what was
  wrong with each model (theory).