Objective: Introduce ElementsObjective: Introduce Elements

A) ElementsA) Elements

1) All things are composed of atoms.1) All things are composed of atoms.

2) The elements include 112 different 2) The elements include 112 different types of atoms, 88 occur naturally.types of atoms, 88 occur naturally.

3) 90% of all atoms are hydrogen.3) 90% of all atoms are hydrogen.

4) Hydrogen atoms are the remnant of 4) Hydrogen atoms are the remnant of stars that exploded.stars that exploded.

5) Complex atoms are formed in stars.5) Complex atoms are formed in stars.

Objective: Introduce ElementsObjective: Introduce Elements

A) Elements (Cont.)A) Elements (Cont.)

6) Living things are made of H, N, O, C.6) Living things are made of H, N, O, C.

7) Atoms are ageless.7) Atoms are ageless.

8) Atoms are smaller than visible light.8) Atoms are smaller than visible light.

9) Brownian motion9) Brownian motion

10) Atoms consist of protons, neutrons, 10) Atoms consist of protons, neutrons, and electrons.and electrons.

Objective: To see how the Thompson Experiment Objective: To see how the Thompson Experiment determined the mass and charge of an determined the mass and charge of an electron.electron.

B) Thomson Experiment.B) Thomson Experiment.1) Vacuum tube was invented near the time 1) Vacuum tube was invented near the time that Benjamin Franklin began experiments that Benjamin Franklin began experiments with electricity, a.k.a. Cathode Ray Tube.with electricity, a.k.a. Cathode Ray Tube.2) Rays were seen when a vacuum tube was 2) Rays were seen when a vacuum tube was connected to electrical current on the ends.connected to electrical current on the ends.3) The rays would bend when an electric field 3) The rays would bend when an electric field was placed nearby. The bending was based was placed nearby. The bending was based on the mass of the particles and the charge.on the mass of the particles and the charge.4) Later determined that the particles were 4) Later determined that the particles were electrons.electrons.

Objective: To determine how the Millikan Objective: To determine how the Millikan Experiment determined the mass of an Experiment determined the mass of an electron.electron.

C) Millikan Experiment.C) Millikan Experiment.

1) Sprayed tiny particles of oil into an 1) Sprayed tiny particles of oil into an electric field.electric field.

2) The particles would float and 2) The particles would float and because they did he was able to because they did he was able to determine their mass and charge.determine their mass and charge.

3) Later determined that the particles 3) Later determined that the particles were electrons.were electrons.

D) The electron.D) The electron.

1) Mass: 9.1 * 10 1) Mass: 9.1 * 10 -31-31 kg kg

2) Negatively charged2) Negatively charged

3) Located on the outer edges of an 3) Located on the outer edges of an atom.atom.

4) Electrons helped determine the 4) Electrons helped determine the properties of the materialproperties of the material

a) chemical reactivitya) chemical reactivity

b) physical properties (taste, color)b) physical properties (taste, color)

H) Electromagnetic Spectrum.H) Electromagnetic Spectrum.

1) Energy released as waves makes up 1) Energy released as waves makes up the electromagnetic spectrum.the electromagnetic spectrum.

2) Electrons that move closer to the 2) Electrons that move closer to the nucleus release energy in the form of nucleus release energy in the form of waves.waves.

3) Electrons require energy to move 3) Electrons require energy to move away from the nucleus of an atom.away from the nucleus of an atom.

4) The different amounts of energy are 4) The different amounts of energy are based on how far or close they move.based on how far or close they move.

H) Electromagnetic SpectrumH) Electromagnetic Spectrum

Lower energy state: QLower energy state: Q22

Higher energy state: QHigher energy state: Q11

Photon energy:Photon energy:QQ11 - Q - Q22

H) Electromagnetic SpectrumH) Electromagnetic Spectrum

1) Waves1) Waves

H) Electromagnetic Spectrum.H) Electromagnetic Spectrum.

Low EnergyLow Energy High EnergyHigh Energy

(See handout)(See handout)

H) Electromagnetic Spectrum:H) Electromagnetic Spectrum:

6) Visable light portion6) Visable light portion

H) Electromagnetic SpectrumH) Electromagnetic Spectrum

5) Comparisons (continued)5) Comparisons (continued)

H) Electromagnetic SpectrumH) Electromagnetic Spectrum

5) Comparisons5) Comparisons

I) Atomic Spectrum.I) Atomic Spectrum.

1) The electrons in 1) The electrons in each atom are each atom are arranged differently.arranged differently.

2) When the 2) When the electrons move they electrons move they emit energy in the emit energy in the form of different form of different colors of light.colors of light.

3) Each atom has 3) Each atom has unique color unique color combination.combination.

Sun Light Spectrum vs. Sun Light Spectrum vs. Hydrogen SpectrumHydrogen Spectrum

Light from the sun or a light bulb has a continuous spectrum

Light from Hydrogen gas has a discrete (non-continuous) spectrum

I) Atomic Spectrum (cont.)I) Atomic Spectrum (cont.)

Each shell can be Each shell can be represented as a layer represented as a layer that an electron can fall.that an electron can fall.

Examples Examples of of

emissions emissions from from

specific specific atomsatoms

The Periodic TableThe Periodic Table

The periodic table is read from top to bottom, left to right, as atomic number increases: 1=H, 2=He, 3=Li, 4=Be, 5=B, 6=C,

and so on.

Elements in columns (groups) have similar

outer-electron configurations, and so tend to behave similarly.

The Periodic The Periodic TableTable

alk

alis

alkali earths

rare earths

halogens

noble gases

transition metals

actinides