HW02 Quy - perlick(app582 HW02 quy(50970 This print-out...

perlick (app582) – HW02 – quy – (50970) 1
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001(part1of3)10.0points
What is the principal quantum number for
the orbital 3 d ?
1. 5
2. 2
3. None of these
4. 6
5. 4
6. 3 correct
Explanation:
n = 3
002(part2of3)10.0points
What is the orbital angular momentum quan-
tum number for the orbital 3 d ?
1. 3
2. 1
3. 0
4. 2 correct
5. 4
6. None of these
Explanation:
ℓ = 2
003(part3of3)10.0points
How many magnetic quantum numbers does
the orbital 3 d have?
1. 5 correct
2. 7
3. None of these
4. 3
5. 9
6. 1
Explanation:
m
ℓ
= - 2 , - 1 , 0 , 1 , 2
004 10.0points
How many total nodal planes are present in
the complete set of 3 d orbitals?
1. 10
2. 3
3. 16
4. 20
5. 8 correct
6. 5
Explanation:
There are 5 orbitals in the 3 d set. 4 of
those orbitals are cloverleaf-shaped and have
2 nodal planes each. That combines to give 8
total nodal planes for the set. The other (5th)
orbital is the d
z 2
orbital which has 2 nodal
cones, not planes.
005 10.0points
How many nodes are present in a 3 s and a 3 p
orbital, respectively?
1. 2 and 1
2. 2 and 2 correct
3. 1 and 1
4. 0 and 2
5. 0 and 1

perlick (app582) – HW02 – quy – (50970) 2
Explanation:
A node is a point, a plane or a three dimen-
sional region of space where the sign of the
wavefunction changes from positive to nega-
tive, (or negative to positive) so it equals zero.
The lowest energy s orbital is 1 s , and this has
no nodes – the wavefunction is always posi-
tive. As we go to the next higher value of n
we add a spherical node, so 2 s would have one
node, and 3 s two. The lowest energy p or-
bital is 2 p ; it has one nodal plane which cuts
through the nucleus (the two ’lobes’ have op-
posite signs). Again, as we go to the next
higher value of n we add a spherical node, so
a 3 p orbital has two nodes.
006 10.0points
The transition metals are elements with par-
tially filled
1. f subshells.
2. p subshells.
3. d subshells. correct
4. s subshells.
Explanation:
In transition metals, d orbitals are being
filled.
007 10.0points
An element with 20 protons and 20 electrons
gains one electron. The electron goes into
what type of orbital?
1. 3 p
2. 3 s
3. 4 s
4. 4 d
5. 4 p
6. 3 d correct
Explanation:
This element has electron configuration
[Ar] 4 s
2
. The next electron goes into the 3 d
orbital according to the Aufbau principle.
008 10.0points
Which element is predicted to have the
ground-state electron configuration [Xe]
4 f
14
5 d
5
6 s
2
?
1. irdium
2. cesium
3. hafnium
4. lutetium
5. tungsten
6. tantalum
7. barium
8. xenon
9. rhenium correct
10. osmium
Explanation:
Remembering the noble gas shorthand,
count all of the superscripts that appear in
the electron configuration. This will give the
number of electrons which in a neutral atom
is equal to the number of protons (atomic
number of the element). Note some excep-
tions do occur in the electron configuration of
atoms because of the stability of either a full
or half-full outermost d -orbital; sometimes an
electron is ‘shuffled’ from the ( n - 1) s orbital.