Download Dr. Steward`s Exam #2 Exam Review (Ch 5, start of 6)

Dr. Steward’s Exam #2 Exam Review (Ch 5, start of 6)
T
T
st
s orbitals are only found in the 1 energy level of an atom because they can have only one orientation.
st
d orbitals are found in the 1 energy level.
F
F
s orbitals are found in every energy level
-1
What is the frequency, in kHz, of a photon with a wavelength of 2.1x10 cm?
10-2 m
= 2.1x10 -3 m
1 cm
2.1x10 -1 cm
ν=
3.00x108 m s
-3
= 1.4x1011Hz
1.4x1011 Hz
2.1x10 m
1 kHz
8
=
3
1.4x10 kHz
10 Hz
Which of the following are true regarding the photoelectric effect? Choose all that apply.
______
__X___
__X___
______
______
During the photoelectric effect process, photons absorb enough energy to become electrons.
The photoelectric effect takes place on the surface of metals.
Einstein was able to explain the photoelectric effect by assuming that light behaved as a particle.
Einstein was able to explain the photoelectric effect by assuming that light behaved as a wave.
Any frequency of light, given enough time, will eject an electron from any element
Which one of the following wavelengths has the lowest frequency?
-7
a. 2.50x10 m
a.
b.
c.
d.
e.
250 nm
-8
2.5x10 km
5000 m
6 cm
-12
1x10 Mm
-5
b. 2.5x10 m
c. 5000 m
-2
d. 6x10 m
-6
e. 1x10 m
Convert everything to the same
unit. In this case, meter would
probably be the easiest. Also,
remember that longest
wavelength = lowest frequency
Which of the wavelengths above would have a photon with the highest energy?
-7
250 nm (2.50x10 m)
Since frequency and wavelength are inversely proportional and energy and
frequency are directly proportional, then wavelength and energy must be
inversely proportional: the shortest wavelength will have the highest energy.
Which orbital of the following has a principal quantum number of 3 and an angular momentum quantum number
of 2?
a.
b.
c.
d.
e.
3s
3d
4f
3f
2p
rd
Must be in the 3 energy level because principle quantum number = 3.
Remember, angular momentum quantum numbers: 0 = s, 1 = p, 2 = d, etc.
th
Which of the orbitals in the previous question cannot exist? 3f cannot exist; f’s don’t start until 4 energy level.
Give the short-hand electron configuration for each of the following atoms/ions:
2
Al: [Ne] 3s 3p
2
3
1
5
V: [Ar] 4s 3d
Cr: [Ar] 4s 3d
2+
1
Cd : [Kr] 3d
10
Remember the anomalous configurations
d-block ions are made by removed electrons from the
s orbital first
Draw orbital diagrams of the outer s and d subshells for:
Cr:
2+
Cd :
Based on the rules learned in class, determine which electron in each pair should have the higher Zeff.
•
•
•
An electron in first energy level of Ti
A valence electron in Na
A valence electron in C
An electron in third energy level of Ti
+
A valence electron in Na
A valence electron in N
What is the maximum number of electrons that the shell with n=1 can accommodate? 2
What is the maximum number of electrons that the shell with n=3 can accommodate? 18
Based on the rules learned in class, determine which ion/atom in each pair has the smaller radius.
•
•
•
•
•
Be
C
Na
C
3N
B
N
+
Na
3N
3P
Below are several principles or concepts and matching descriptions. Which answer correctly matches the entries in
the two columns?
principle
description
1. Heisenberg Uncertainty
Principle
a. Bodies can lose energy only in quantized amounts.
2. Pauli Exclusion Principle
b. It is impossible to determine simultaneously the position and speed of a particle
with extreme accuracy.
3. Hund's Rule
c. The electrons in a given atom must differ in the value of at least one of their 4
quantum numbers.
4. Planck's Hypothesis
d. Electrons fill orbitals with the same energy so that one e occupies a different
orbital before any orbital is occupied by 2 e .
-
Which of the following rules is being broken in the orbital diagram to the
right? Choose all that apply
____ Pauli Exclusion Principle
__X_ Hund’s Rule
____ Einstein’s Code of Conduct
____ Photoelectric Effect
____ Wave Particle Duality