ChemistryWiki | RecentChanges | Preferences
1. a) Atoms are the smallest particle of matter (it is indivisible).
b) Atoms of the same element are identical including mass.
c) Atoms of different elements are different including mass.
d) Atoms combine to form compounds in a simple whole number ratio
2. a. Total number of atoms are conserved.
b. Number of each type of atom are conserved.
3. Since the green glow (that is coming out of the metal atoms) bend to the positive end of the magnet, it showed that it was a negative particles called an electron. He changed the power of the magnet and the glow bend more less that explains that the charge to mass ratio of the electron was a constant. This indicates that there is only one type of electron.
4. Milikian used an oil dropping experiment to determine the exact mass and charge of the electron.
Goldstein discovered the proton and Chadwick discovered neutron.
5. *Proton (p+), positively charged, mass = 1.67E-24 g, located in nucleus
- Neutron (n0), neutral charge, mass = 1.67E-24 g, located in nucleus
- Electron (e-), negatively charged, mass = 9.11E-28 g, located outside nucleus
- electron mass is approximately 1/2.0E3 mass of proton or neutron (actually is 1/1.84E3)
- Note: Yes, these subatomic particles are made up of even smaller particle, but that is for physic to explain NOT chemistry.
6. a. 8 of 9 particles deflects 0-5 degree (particles go straight thru) means that "particles" volume is small compared to volume of an atoms. Thereby, rest of atom is mostly empty space.
b. Greater than 105 degree deflection indicates that the small volume "particle" is very massive (most all mass of atom)
c. All angles of deflection between 0 and 105 indicate that the small volume mass "thing" is positively charged
7. Volume of atom is approximately 1.0E4times more volume than the volume of the nucleus.
8. Rutherford's Shortcoming: Electron's revolve (orbit in a defined distance) around the nucleus like planets around the sun
9. a. How the electrons move outside nucleus (energy of electron = distance electron away from nucleus) and how atoms & energy interact.
10. atom is at the ground state (all electron in the lowest energy available). Atom absorb a specific amount of energy that allows the electron to absorb this energy ad it will jump to a higher energy level (atom is now in excited state). Instantaneously, the electron fall back down to the original lower energy level (atom is back in the ground state) releasing (called emitted) the exact amount of energy that was originally absorbed.
The part of Bohr's theory that is incorrect is that electrons do not revolve around the nucleus like planets around the sun (specific orbit).
11. 7 energy levels correspond to the 7 rows on the Periodic Table
12. Bohr still said that the electron revolve around the nucleus like planets around the sun (only this time it is on surface of energy level).
13. Planck state that energy is made up of particles (called quanta) and that energy particle size is directly related to its frequency. Debroglie stated that energy is both a particle and a wave at the same time (called Duality of Light).
14. Bright line spectrum is unique for every atom (fingerprint of the atom). Each colored line indicates an electron falling back down to original lower energy from the higher energy level and a specific amount of energy is emitted.
15. Infrared, R (700nm) O Y G B I V (400nm), Ultraviolet
16. Planck's Demo
17. 85.5g C
18. f = 7.02E14 Hz, 4.28E-7m, 428nm, Blue