Post on 19-Jan-2016
transcript
Agenda
• Elements/AT/Atoms, Ions, & Isotopes
• Homework Check
• Song
• Notes
• Go over Test
• Homework
Who developed an atomic theory?
John Dalton
What were his four points?
Who found the e-?
Thompson
Who found the n0?
Chadwick
Who found the p+?
Goldstein
Who discover the nucleus?
Rutherford
What experiment did he do?
gold foil experiment
What type of model did Bohr develop for the atom?
planetary model
Who came up with the idea of an e- cloud?
Schrödinger
141466CC
pp++
nnoo
ee--
2072078282PbPb+4+4
pp++
nnoo
ee--
Atomic Theory Polka• Dalton, Thomson, Rutherford and Bohr.
Schrödinger and Heisenberg, and many, many more. Used their brains to venture in the realm of inner space and found the world of the atom was a weird and wondrous place.
• Dalton did experiments and said, “I think it’s clear, atoms are tiny indestructible spheres.”
• Thomson worked with cathode rays and said, “I disagree. A plum-pudding model makes much more sense to me.”
• A new chapter in atomic theory started to unfold when Rutherford played around with atoms made of gold. When a few of his alpha particles came bounding back, he hypothesized a nucleus had knocked them off the track.
• Dalton, Thomson, Rutherford and Bohr. Schrödinger and Heisenberg, and many, many more. Used their brains to venture in the realm of inner space and found the world of the atom was a weird and wondrous place.
• Bohr saw spectral lines for hydrogen and said, “It seems to me.. Electrons move in orbits with specific energies.”
electron
neutron
proton
• Heisenberg said, “Forget it, there’s no way to know the orbit or a path, where the electron’s gonna go.”
• Schrödinger used lots and lots of fancy mathematics, and made a model of the atom based on quantum mechanics. It has orbitals and those are based on probability. The atom is a fuzzy blob of pure uncertainty.
• Dalton, Thomson, Rutherford and Bohr. Schroedinger and Heisenburg, and many, many more. Used their brains to venture in the realm of inner space and found the world of the atom was a weird and wondrous place.
Homework# Isotope Nuclide A # M # #p+ #n0 #e-
1 Copper-65 6529Cu+ 29 65 29 36 28
2 Lithium-7 73Li+ 3 7 3 4 2
3 Neon-20 2010Ne 10 20 10 10 10
4 Oxygen-16 168O-2 8 16 8 8 10
5 Chlorine-36 3617Cl- 17 36 17 19 18
6 Scandium-45 4521Sc+3 21 45 21 24 18
7 Calcium-40 4020Ca+2 20 40 20 20 18
8 Bromine-80 8035Br- 35 80 35 45 36
9 Tellurium-128 12852Te-2 52 128 52 76 54
10 Aluminum-27 2713Al+3 13 27 13 14 10
Homework# Isotope Nuclide A # M # #p+ #n0 #e-
11 Zinc-65 6530Zn+2 30 65 30 35 28
12 Iron-56 5626Fe+2 26 56 26 30 24
13 Iron-55 5526Fe+3 26 55 26 29 23
14 Phosphorus-31 3115P-3 15 31 15 16 18
15 Xenon-131 13154Xe 54 131 54 77 54
16 Magnesium-24 2412Mg+2 12 24 12 12 10
17 Carbon-12 126C-4 6 12 6 6 10
18 Hydrogen-3 31H+ 1 3 1 2 0
19 Sodium-24 2411Na+ 11 24 11 13 10
20 Hydrogen-1 11H- 1 1 1 0 2
Bohr’s Model
Date
Planetary Model
• Bohr described the atom through a planetary model
• e- orbit the nucleus like planets around the sun
• They are located in specific energy levels or shells in concentric circles like layers of an onion
Shells
• 1st shell• 2nd shell• 3rd shell• 4th shell
• 2• 8• 8 (18)• 8 (32)
• Each shell has a specific number of electrons it can hold
11H
126C
2311Na
Practice
Lewis Dot Structure
• Lewis came up with a simple method of showing the outer shell of an atom
• First write the symbol of the element
• Next figure out how many e- are in the outer shell
• Finally put that many dots around the symbol
Examples
H
C
Na
Na+
2311K+
K
168O-2
O
3517Cl-
Cl
4018Ar
Ar
3216S-2
S
Transitional Metals
• Transitional metals put their first two e- in the nth shell (where n is the row number)
• They then put the rest of the electrons back into the n-1 shell
Example
• Sc has 21 e-
• The first 18 work the same as we have been doing
• That leaves 3 e-
Example
• Sc is in the 4th row so we put two of the remaining electrons in the 4th shell
Example
• Since it is in the 4th row n-1=3
• So we put the last electron in the 3 shell