Download 1. Millikan did his experiments with the balance of

1. Millikan did his experiments with the balance of forces between the gravitational and electrical
forces on a small drop of oil that lies between two electrode plates. By knowing the size of an
electric field, the charge on the drops of oil that was dropped (droplets) can be determined. By
repeating this experiment several times, he found that the values measured are always multiples
of the same number. He then interpreted that this number is the charge of an electron: 1602 ×
10-19 coulomb (SI unit for electric charge).
2. Ionic compounds can be neutral, if they consist of positive and negative ions, because the
number of protons in the nucleus equals the number of electrons surrounding the nucleus.
3. As a particle, a photon can only interact with matter by transferring the energy of :
Where h is Planck's constant, c is the speed of light, and λ is the wavelength.
So, the increase of energy is inversely proportional to the wavelength. The longer wavelengths,
the smaller the energy.
Looking that formula, we can rank the follwing photons by the increasing energy like this :
1. red (λ=660 nm)
2. yellow (λ=595 nm)
3. blue (λ=453 nm)
4. a.) n=1, l=0, ml=0 (CORRECT)
b.) n=2, l=2, ml=+1 (INCORRECT)
correction : n= 2, l=1, ml=+1 or n=3, l=2, ml= +1
c.) n=7, l=1, ml=+2 (INCORRECT)
correction : n=7, l=1, ml=+1 or n=7, l=1, ml=-1
d.) n=3, l=1, ml=-2 (INCORRECT)
correction : n=3, l=1, ml=-1 or n=3, l=2, ml=-2
5. a.) Quantum numbers for outermost electron in an Li atom :
n=2, l=0, ml=0
b.) Quantum number if the electron gained when a Br atom becomes a Br- ion :
n=4, l=1, ml=+1
c.) Quantum number if the electron lost when a Cs atom ionizes :
n=4, l=1, ml=+1
d.) Quantum number for highest energy electron in the ground-state B atom :
n=2, l=1, ml=-1
6. a.) The condensed ground-state electron configuration of Mo3+ : [Kr] 5s2, 4d1
Mo3+ is paramagnetic because in the d orbital there are unpaired electrons.
b.) The condensed ground-state electron configuration of Au+ : [Xe] 6s2, 4f14,5d8
Au+ is paramagnetic because in the d orbital there are unpaired electrons.
c.) The condensed ground-state electron configuration of Mn2+ : [Ar] 4s2, 3d3
Mn2+ is paramagnetic because in the d orbital there are unpaired electrons.
d.) The condensed ground-state electron configuration of Hf2+ : [Xe] 6s2, 4f14
Hf2+ paramagnetic because in the d orbital there are unpaired electrons.
7. Because Germanium radius are smaller than the radius of Gallium, so the first ionization energy
(IE1) Germanium is greater than the first ionization energy (IE1) Gallium. So also with IE2,
IE3, and IE4 which contained in Germanium and Gallium.
8. In a chemical bond the outer electrons are closer each other. More large atomic radius, the
farther the distance is also the core with the outer electrons, so small energy produced. Then
when that kind of bonded atoms, the bond will form weak.