260 likes | 341 Views
Atomic Structure. Daniel R. Barnes Init: sometime about a year before 10/4/2006. What are atoms made of?. Subatomic Particles. proton. mass = 1.007 amu. charge = + 1. mass = 1.009 amu. neutron. charge = 0 = “neutral”. mass = 0.000549 amu. electron. charge = -1.
E N D
Atomic Structure Daniel R. Barnes Init: sometime about a year before 10/4/2006
What are atoms made of?
Subatomic Particles proton mass = 1.007 amu charge = + 1 mass = 1.009 amu neutron charge = 0 = “neutral” mass = 0.000549 amu electron charge = -1
Which two particles are the heaviest? proton mass = 1.007 amu mass = 1.007 amu charge = + 1 mass = 1.009 amu neutron mass = 1.009 amu charge = 0 = “neutral” mass = 0.000549 amu mass = 0.000549 amu electron charge = -1
neutral, so # = # 3 Li 3 3 Li 6.94 7S -3 4 "shell" or "energy level" nucleus
neutral, so # = # 3 Li 3 3 Li 6.94 7S -3 4 nucleus Which two particles are the heaviest? Where is almost all the mass located?
Who discovered the nucleus? When he discovered the nucleus, what did he figure out about it? Ernest Rutherford, 1907 Just how small is an atomic nucleus? He figured out that it was positively-charged, and that it was very small. well . . .
Here is the Los Angeles Memorial Coliseum as seen from a satellite. Click here to go to the website from which this image was taken.
Can you imagine a marble on the 50-yard line? That’s how small the nucleus of an atom is compared to the atom as a whole.
So, what’s wrong with the way I drew this atom? The nucleus is far too large. Let’s shrink it. Is that small enough? Okay. Let’s shrink it again, then.
Is that small enough for you? An atom may be tiny, but it’s gigantic compared to the nucleus in its center. Let’s shrink it again, then. Empty space Okay. Is THAT small enough? That’s pretty strange, considering that the nucleus is where over 99% of the atom’s mass is. Why not? Yep. If you can see it, I drew it too big. Atoms are made mostly of . . .
Is that small enough for you? An atom may be tiny, but it’s gigantic compared to the nucleus in its center. Let’s shrink it again, then. Empty space Okay. Is THAT small enough? That’s pretty strange, considering that the nucleus is where over 99% of the atom’s mass is. Why not? Yep. If you can see it, I drew it too big. Atoms are made mostly of . . .
Empty space And you’re made of atoms, so . . .
Hey, Mr. Barnes! I got a question! . . . YOU’RE made mostly of empty space.
If I’m made mostly of empty space, And you’re made mostly of empty space . . .
Historical Trivia Time!
Who discovered the electron? Joseph John Thomson, in or before 1897
Time to draw some more atoms
neutral, so # = # 1 H 2 1 1 H 1.01 2S -1 1
2 missing , so 4 – 2 = 2 2+ Be 4 4 Be 9.01 9S -4 5
2 extra , so 8 + 2 = 10 2- O 8 8 O 16.00 16S - 8 8
3 extra , so 6 + 3 = 9 3- C 13 6 6 C 12.01 13S - 6 7