1. What subatomic particle is not located in the nucleus?
BELL RINGER
What subatomic particle is not located in the nucleus?

2. Atomic History Research
Chapter 3
Review Book – Topic 1
Chapter 1

3. What are the nucleons (things in the nucleus)?
BELL RINGER
What are the nucleons (things in the nucleus)?

4. Quiz Who did the gold foil experiment? Who first named an atom?
According to Bohr, where are electrons located?
Draw an atom according to Democritus.
Who discovered the electron?

5. History - Greeks Earth, Wind, Water, Fire!
A. Ancient Greece (2000+ years ago)
Democritus
- believed that matter could not be continuously divided
- Matter consists of small indivisible particles
“Atomos” = Atom  indivisible
- Aristotle did not agree  his teacher
Particles are in continuous motion
Four elements make up all matter and energy
Earth,
Wind,
Water,
Fire!
No scientific evidence to show this.

6. History by 1700s (scientific revolution), all chemists agreed:
on the existence of atoms
that atoms combined to make compounds

7. History - Dalton B. Dalton’s Atomic Theory - 1803
1. All matter is composed of small particles which cannot be broken down
(atoms)  same as Democritus
2. All atoms of the same element are identical in size, mass and properties. Atoms of different elements are different in size, mass and properties
Sulfur
Hydrogen
3.Atoms of different element combine in simple ratios to make compounds
PbO2
H2S
4. In chemical reactions, atoms are combined, separated, or rearranged (No atoms are created or destroyed)
So at this point, we believe that an atom is like a small solid ball of matter that cannot be split up

8. Dalton's Amendment's
Some parts of Dalton’s theory were wrong:  AMENDMENTS
atoms are divisible into smaller particles (subatomic particles)
atoms of the same element can have different masses (isotopes)
Matter can be lost - Nuclear

9. DISCOVORED THE ELECTRON
History - Thomson
C. J.J. Thomson
Experimented with cathode rays
Used electric field to show that cathode rays are negatively charged particles
DISCOVORED THE ELECTRON
After discovery of the proton, Thomson assumed an atom was a mixture of + and – charged particles, all mixed up
Plum-Pudding Model
+ -

10. History - Rutherford Screen D. Rutherford Gold foil Radioactive source
Ernest Rutherford wanted to determine what an atom looked like.
Fired (+) charged alpha particles at a very thin piece of gold (Gold foil)
Put a screen behind the foil to determine what happens to the rays
Gold foil
Screen
Radioactive source
Click on me!!!
Most of the rays went straight through the foil
Some rays deflected
A very few rays came straight back

11. History - Rutherford Rutherford explained this by stating that
a. Atoms have mostly empty space
This is why most rays went straight through
b. There must be a dense positive center to an atom
This is why the positive rays deflected. (Positive rays are repelled by positive charged objects) +
Rutherford
model
Later experiments showed that electrons exist in the space between nuclei

13. Subatomic Particles includes all particles inside atom
proton
electron
neutron
charge on protons and electrons are equal but opposite
to make an atom neutral, need equal numbers of protons and electrons

14. number of protons identifies the atom as a certain element
Subatomic Particles
number of protons identifies the atom as a certain element
protons and neutrons are about same size
electrons are much smaller

15. Subatomic Particles
# protons = atomic number
# electrons = # of protons (for now)
# neutrons =
mass number– atomic number

16. Examples
p n e Li 3 7 3 4 3 Na 11 23 11 12 11 Be 4 9 4 5 4 Fe 26 56 26 30 26

17. Give the p, n, and e in a neutral atom of Silver.
BELL RINGER
Give the p, n, and e in a neutral atom of Silver.

18. p n e Cl Hg Xe X Some more practice 17 17 18 17 201 80 121 80 54 77 5422 22 26 22

19. Structure of the Atom Nucleus: Electron Cloud:
contains protons and neutrons
takes up very little space
Electron Cloud:
contains electrons
takes up most of space

20. History - Bohr E. Bohr - looked at the arrangement of electrons 3 2 1
Electrons exist in definite areas around the nucleus
Energy levels e- e- e- e-
Further from the nucleus, an electron has more energy
Electrons can gain energy and “jump” to higher levels
nucleus
They can then give off the energy as they jump back down
Energy levels are numbered 1,2,3,4,5,6,7
With 1 being closest to the nucleus and having the least amount of energy
Planetary model +
All atoms have the same types of energy levels

21. History - Wave Mechanical Model
F. Wave Mechanical Model
Dr. Wave Mechanical
Aka – ‘Electron Cloud’
Modified Bohr’s model
Electrons are not in circular orbits, but exist in specific spaces around the nucleus
nucleus
Pattern is random, unpredictable
most dense near nucleus
level
level
Energy levels contain sublevels

22. Review of Atoms Dalton Bohr Thompson Rutherford Democritus
Wave Mechanical

23. Electron Location Located in energy levels outside of the nucleus
The closer to the nucleus = less energy
The farther away from the nucleus = more energy

24. Electron Location 2n2 Energy level 1 can have -
Electrons are located in energy levels or shells. There are a bunch of energy levels and each level can “fit” only a limited number of electrons.
2n2
Where ‘n’ represents the energy level
Energy level 1 can have -
Energy level 2 can have -
Energy level 3 can have -
Energy level 4 can have -
2 e-
8 e-
18 e-
32 e-

25. Bohr Diagrams Gives the location and the number of the p, n, and e.
Draw the Bohr diagram for Oxygen: p= n= 8 8
Valence e- = 6

26. Answer p= n= 9 10
Valence e- = 7

27. What did Rutherford contribute to the development of the atom?
BELL RINGER
What did Rutherford contribute to the development of the atom?

28. Quiz Ge
Manganese As
Phosphorus Ti
Sodium Cr
Krypton Be
Boron

29. The above is an example of a ground state electron configuration
(=the configuration on your R.T.’s)

30. Each electron in an atom has its own distinct amount of energy
Each electron in an atom has its own distinct amount of energy. Electrons in the first energy level have the lowest potential energy since they are located closest to the nucleus.

31. As an electron gains a specific bunch of energy, the electron “jumps” to a higher energy state (excited state). p= n= 10
Excited State
e- Configuration for Ne
2-7-1 p= n= 10
Ground State
e- Configuration for Ne
2-8

32. How is light produced? Gives off Absorbs nrg Releases nrg p= n= 10 p=
Excited State
e- Configuration for Ne
2-7-1
Absorbs nrg p= n= 10
Releases nrg
Gives off
Ground State
e- Configuration for Ne
2-8

33. When an electron returns from a higher energy state to a lower energy state, a specific amount of energy is given off --> RELEASED

34. Each element gives off a certain color or spectrum of colors.
You can identify unknown elements by the color of light that they give off.
Bohr Animation

35. Ions The number of protons never changes in an atom.
So far we have only talked about electrically neutral atoms, atoms with no positive or negative charge on them. 
Atoms, however, can have electrical charges – They can gain/lose e-.  Some atoms can either gain or lose electrons
The number of protons never changes in an atom. 

36. Ions If an atom gains electrons, the atom becomes negatively charged.
If the atom loses electrons, the atom becomes positively charged (because the number of positively charged protons will exceed the number of electrons). 
An atom that carries an electrical charge is called an ion. 

37. Ions
 Listed below are three forms of hydrogen; 2 ions and the electrically neutral form.
H+ : a positively
charged
hydrogen ion
H- : a negatively
charged
hydrogen ion
H : the
hydrogen atom

38. Ions H+ : a positively H- : a negatively charged charged hydrogen ion
Neither the number of protons nor neutrons changes in any of these ions, therefore both the atomic number and the atomic mass remain the same.
H+ : a positively
charged
hydrogen ion
H- : a negatively
charged
hydrogen ion
H : the
hydrogen atom

39. Identify the number of subatomic particles in the following ions:
A.) Na+ B.) F- C.) O-2 p n e 11 9 8 12 10 8 10 10 10

40. Which is the electron configuration of an atom in the excited state?
BELL RINGER
Which is the electron configuration of an atom in the excited state?
2-8-2
2-8-1
2-7-1
2-8-3

41. Timeline Activity

42. When subjected to a flame, solutions containing certain metals have characteristic colors corresponding to the energy released when excited electrons return to lower energy levels.

43. Flame Test Lab

44. Identify the number of subatomic particles in the following ions:
A.) Mg B.) Br- C.) K+ p n e 12 35 19 12 45 20 36 18 10

45. Draw the Bohr diagram for a F-1 ion.
BELL RINGER
Draw the Bohr diagram for a F-1 ion.

46. Isotopes atoms of the same element with different numbers of neutrons
most elements exist as a mixture of isotopes
Disproves Dalton’s theory
What do the Carbon isotopes below have in common? What is different about them?

47. How many protons do each of the hydrogen atoms below have?
Mass Number
sum of the particles in nucleus
= #p + #n
This is a whole number!!!
How many protons do each of the hydrogen atoms below have?

48. Ions/Isotopes
PRACTICE PROBLEMS

49. Relative Atomic Mass
since masses of atoms are so small, it is more convenient to use relative atomic masses instead of real masses
to set up a scale, we have to pick one atom to be the standard
since 1961, the carbon-12 nuclide is the standard and is assigned a mass of exactly 12 amu (=atomic mass unit)
REFERENCE TABLES

50. Relative Atomic Mass
atomic mass unit (amu)- one is exactly 1/12th of the mass of a carbon-12 atom
mass of proton= amu = 1 amu
mass of neutron= amu = 1amu
mass of electron= amu = 0 amu

51. Average Atomic Mass
weighted relative atomic masses of the isotopes of each element
each isotope has a known natural occurrence (percentage of that elements’ atoms)

52. Calculating Average Atomic Mass
An element has three main isotopes with the following percent occurances:
#1: amu, 90.51%
#2: amu, 0.27%
#3: amu, 9.22%
Find the average atomic mass and determine the element.
= amu

53. Calculating Average Atomic Mass
Naturally occurring copper consists of:
Cu-63
Cu-65
Actual Mass
62.929amu
64.927amu
Percent
Abundance
Relative abundance
Relative Mass
69.71% 30.83%
.6971
.3083
1.0054
43.87
20.02
63.89

54. Calculate the average atomic mass of Sulfur.
BELL RINGER
Isotope
AMU
Natural Abundance
32S
31.97
94.93%
33S
32.97
0.76%
34S
33.97
4.29%
36S
35.97
0.02%
Calculate the average atomic mass of Sulfur.
32.06 amu

55. Average Atomic Mass
There are two isotopes of Silver, Ag-107 and Ag % of the isotopes are Ag-107, what is the average atomic mass of silver?
Ag-107
52% =
5564 =
Ag-109
48%
5232
10796 ÷
100
=107.96

56. Beanium

57. Identify the number of p, n, and e in the following:
BELL RINGER
Identify the number of p, n, and e in the following:

58. Spectroscopy

60. The energy emitted is in the form of radiant or light energy which corresponds to a bright-line spectrum. Each element has its own signature or bright-line spectrum.

61. There are several kinds of spectra, such as: continuous & bright line.
A continuous spectrum is, as the name implies, a parade of all the colors from the deepest red to the ultraviolet - of which the rainbow in the sky is a good example. 

62. In the laboratory, a continuous spectrum can be produced by heating a solid - Light from the electric lamp filament, for example, produces such a spectrum.

63. When light emitted by a gas through which an electrical discharge is passing produces a spectrum consisting of a few isolated parallel lines, it is known as a "bright line spectrum"  

64. The characteristic color of neon signs is due to bright red and orange lines in its spectrum. The typical color of neon signs is due to the great intensity of the red and orange lines.

65. A group of elements would create a combination of spectral lines
Element X
3 different electron jumps
Element Y
Elements X and Y combined
Notice how the combination of X and Y is just a combination of the individual spectral lines?

66. Some Atomic Emission Spectra
Hydrogen
Mercury
Argon
Helium

67. It should be carefully noted that each element always gives the same pattern of lines.  Each element, so to speak, has its own fingerprints, possessed by no other element.  This fact is utilized in chemical analysis and in many other applied fields.

68. Identify the number of electrons and neutrons in the following:
BELL RINGER
Identify the number of electrons and neutrons in the following:
Ti +3
S-2

69. What element is the unknown?

70. Atomic History DEMOCRITUS named the most basic particle
atom- means “indivisible

71. Atomic History
DALTON
Atoms of same element have the same size, mass, and properties
Atoms can’t be subdivided, created or destroyed
Atoms of different element combine in whole number ratios to make compounds
In chemical reactions, atoms are combined, separated, and rearranged.

72. Atomic History DALTON Some parts of Dalton’s theory were wrong:
atoms are divisible into smaller particles (subatomic particles)
atoms of the same element can have different masses (isotopes)
Most important parts of atomic theory:
all matter is made of atoms
atoms of different elements have different properties

73. Atomic History RUTHERFORD ‘Gold Foil Experiment’
Atom is mostly empty space
Small, hard, dense positive part = NUCLEUS

74. Atomic History
JJ THOMSON
discovered the e-

75. Atomic History
NEILS BOHR
Electons in ‘orbit’
protons in nucleus

76. Atomic History MODERN MODEL protons in nucleus
Electrons in an orbital – most probable location

77. Atomic History SUMMARY
What we know about the atom has been the work of many scientists over thousands of years!

79. WHITE BOARD REVIEW

80. Get the formula from Reference Tables
BELL RINGER
How much heat energy in joules is released by 25.0 grams of water when it is cooled from 75.2ºC to 31.9 ºC?
Get the formula from Reference Tables
q = mcΔT
q = 25.0g (4.18J/g•ºC) 43.3ºC
q = 4525 J