History of the Atom Activity

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History of the Atom Activity
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• Objectives
• Today I will be able to
• Explore the nature of science by completing an
  activity
• Research a scientist to understand the history of
  the atom
• Informal assessment monitoring group
  interactions and questions
• Formal assessment analyzing student responses
  to the exit ticket
• Common Core Connection
• Build Strong Content Knowledge
• Value Evidence
• Come to understand other perspectives and
  cultures

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Lesson Sequence

• Evaluate Warm Up
• Explore History of the Atom Research
• Enage Construction of Timeline
• Elaborate Gallery Walk
• Evaluate Exit Ticket

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Warm - Up

• Using all of the pieces, except the piece with
  the x, arrange the pieces into the shape of a
  square.
• You discover a missing piece to the puzzle. Work
  by yourself to fit the new piece in and make a
  new square.
• How does this relate to making a discovery in
  science?

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Warm - Up

• Complete the half sheet on atomic changes
• Use the word bank on the worksheet to complete
  the questions

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Warm - Up

• Complete the Ions/ Isotope WS
• Dont worry its not a quiz ?

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Warm - Up

• What did the gold foil experiment help determine?
• What is the difference between the Bohr and
  Schrodinger models of the atom?

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Objective

• Today I will be able to
• Explore the nature of science by researching the
  history of the atom
• Research a scientist to understand the history of
  the atom

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Homework

• Review the information on your scientist
• Continue researching

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Agenda

• Warm Up
• History of the Atom Research
• Construction of Analogies
• Make a Flip Book
• Exit Ticket

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History of the Atom Research

• Each member of the group will use textbooks and
  the computers to research their two assigned
  scientists

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Analogies
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Make an analogy

• Work with your group to create a real-life
  analogy for the Dalton, Thomson, Bohr and
  Schrodinger Models of the atom
• Look at Ms. Oses example for guidance
• Share analogies with the class

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History of the Atom Analogy

• Daltons Model
• Thomsons Model

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History of the Atom Analogy

• Bohr Model
• Sugar cookie with chocolate chips in rings around
  the outside
• Schrodinger Model
• Sugar cookie dipped in melted chocolate

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Make a flip book

• The image of your analogy must be included in the
  flip book

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Flipbook Requirements

• For Dalton, Thompson, Rutherford, Bohr,
  Schrodinger
• Describe their model of the atom
• Draw a picture of their model of the atom
• Write and draw a picture of your analogy
• For Thompson and Rutherford Describe the
  experiment
• For Dalton Write the pieces of the atomic
  theory

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History of the Atom Notes
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Democritus (400 BC)

• Greek Philosopher
• All matter is composed of tiny, indivisible parts
  called atomos
• He said you cannot cut a piece of matter
  infinitely, but at some point you would get the
  smallest piece of matter possible.
• Said atomos could not be divided any further

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John Dalton (1803)

• School Teacher
• Studied the ratios in which elements combine in a
  chemical reaction
• Daltons Atomic Theory
• All matter is composed of tiny indivisible parts
  called atoms (they can be broken down further,
  although properties will not be retained)
• Atoms of the same element are exactly alike,
  atoms of different elements are different (not
  all atoms of the same element have the same mass
  isotopes)
• Atoms can combine in simple ratios to form
  compounds
• Atoms are neither created nor destroyed
• - Atoms cannot be destroyed, they simply
  rearrange in a chemical change, therefore the
  total amount of atoms remains the same

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John Dalton (1800s)
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J.J. Thomson (1897)

• Discovered the electron
• Worked with Cathode Ray Tubes
• Discovered particles with a negative charge,
  electrons knew they were negative charges by
  the deflection of the beam from a magnet
• He also was able to estimate that the mass of the
  electron was equal to about 1/1800 of the mass of
  a hydrogen atom.
• His discovery of the electron won the Nobel Prize
  in 1906.
• He created the plum pudding model of the atom.
• Pudding is positive
• Electrons are embedded within the pudding

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J.J. Thomson (1897)
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J.J. Thomson (1897)

• Discovered that the beam going between the anode
  and cathode could be deflected by bringing a
  magnet close to the cathode ray tube. The
  deflection that Thomson observed showed that the
  beam must have been made up of negatively charged
  particles
• He showed that the production of the cathode ray
  was not dependent on the type of gas in the tube,
  or the type of metal used for the electrodes. He
  concluded that these particles were part of every
  atom.

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Robert Millikan (1909)

• measured the charge of an electron using the oil
  drop experiment.
• x-rays gave the oil a negative electron
• 1.60x10-19 coulomb is the charge of an electron
• using Thomsons charge to mass ratio, he
  determined the mass of the electron is
  9.11x10-28g

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Oil Drop Experiment
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Ernest Rutherford (1911)

• Born in New Zealand 1871-1937
• Tested Thomsons theory of atomic structure with
  the gold foil experiment in 1910.
• Bombarded thin gold foil with a beam of alpha
  particles.
• If the positive charge was evenly spread out, the
  beam should have easily passed through.
• All of the positive charge and most of the mass
  of an atom are concentrated in a small core,
  called the nucleus.
• Gold Foil Experiment (alpha scattering)
• he determined that an atoms positive charge and
  most of its mass was concentrated in the core
  (most of the atom is empty space)
• he named the core the nucleus

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Rutherfords Gold Foil Experiment
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Rutherfords Model of the Atom

• Contained a positive nucleus
• Electrons were around the outside of the nucleus

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Niels Bohr (1914)

• Start of the Quantum Mechanical Model
• Electrons are particles
• Electrons occupy different fields or energy
  levels
• Based on the fact that atoms appeared to release
  fixed amounts (quantized) of energy when exposed
  to heat
• When an electron is exposed to an energy source,
  it jumps to a higher energy level
• When the electron eventually falls back to its
  original position, energy is released

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Niels Bohr (1914)
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Werner Heisenberg

• Principle of uncertainty
• We cannot know both the location and the momentum
  of an electron
• The more we know about an electrons position,
  the less uncertain we are

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Erwin Schrödinger (1926)

• Based on Heisenberg's principle of uncertainty
• Shows where electrons will probably be found by
  using the waves they leave behind
• Electrons are waves
• Update to the Quantum Mechanical Model
• Sometimes called the Electron Cloud Model

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Erwin Schrödinger (1926)
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Exit Ticket

• Write two facts that you learned today about a
  scientist that another group member researched

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Exit Ticket

• What does this activity teach us about the nature
  of scientific knowledge?