Exam Three Flashcards
(86 cards)
1
Q
Pi/Sigma bonds within a double bond:
A
one pi bond and one sigma
2
Q
Pi/Sigma bonds within a triple bond:
A
two pi bonds and one sigma
3
Q
Which elements can have an expanded octet (provide example for each.
A
- phosphorus (PCl5)
- sulfur (SF6)
- chlorine (ClF3)
- sulfate ion
- sulfate oxides
4
Q
What compounds can have a deficient octet?
A
- BeCl2
* *central atom has 2 sigma bonds - BF3
* *central atom has 3 sigma bonds
5
Q
What compound have a weird octet?
A
NO2
**due to lone electron
6
Q
Class of a linear geometry:
A
AX2 or AX2E3
7
Q
Example of linear geometry (3):
A
BeF2, HCN, CO2
8
Q
Ideal bond angle of a linear geometry:
A
180
9
Q
Class of trigonal planar:
A
AX3
10
Q
Ideal bond angle of trigonal planar:
A
about 120
11
Q
Class of bent:
A
AX2E or AX2E2
12
Q
What do lone pairs do to the bond angle?
A
causes deviation, angle will be less than the ideal value
13
Q
Tetrahedral electron group arrangement can have how many shapes?
A
3
14
Q
Class of tetrahedral:
A
AX4
15
Q
Class of trigonal pyramidal:
A
AX3E
16
Q
Ideal bond angle of tetrahedral arrangments:
A
about 109.5
17
Q
Trigonal bipyramidal electron group arrangement can have how many shapes?
A
4
18
Q
Class of trigonal bipyramidal:
A
AX5
19
Q
Class of seesaw:
A
AX4E
20
Q
Class of t-shape:
A
AX3E2
21
Q
Ideal bond angle of trigonal bipyramidal arrangments:
A
about 120 and 90
- *t-shaped is 90
- *linear is 180
22
Q
Octahedral electron group arrangement can have how many shapes?
A
3
23
Q
Class of octahedral:
A
AX6
24
Q
Class of square pyramidal:
A
AX5E
25
Class of square planar:
AX4E2
26
Ideal bond angle of octahedral arrangement:
about 90
27
Period(s) [...] can form more than four bonds.
3-6
28
Formal charge:
valence - sticks - dots
29
As you go L to R across the periodic table, the atomic size...
decreases
**nucleus to electron attraction (Zeff)
30
As you go down the periodic table, the atomic size...
increases
**adding more orbitals
31
Down a group [...] dominates due to [...].
Across a period [...] dominates because [...] remains the same and electrons pull closer to [...]..
n (quantum number); electron shielding;
Zeff (effective nuclear charge); electron shielding; the nucleus
32
What is electron shielding? How does this affect the periodic trend?
inner layers of electrons shield the outer electrons
33
Down a transition series, atomic size [...] from Period 4 to 5 and [...] from 5 to 6.
increases slightly; none
34
Across a transition series, atomic size [...] through the first two or three elements.
shrinks
35
After the first 2/3 elements in the transition series, the atomic size...
remains constant
36
Size of V (23) compared to Zn (30):
same
**transition metals going across a series remain constant
37
Atoms with a low IE tend to form [...] while those with a high IE tend to form [...] (except for [...]).
cations; anions; noble gases
38
Ionization energy:
requirement to completely remove 1 mol of electrons from 1 mol of atoms/ions
39
Ionization energy is to overcome the [...].
electrostatic attraction
40
As size decreases, it takes [...] energy to remove an electron.
more
41
Electronegativity is inversely related to [...]. So across the periodic table, EN [...] while down the table, EN [...].
atomic size; increases; decreases
42
Pauli exclusion principle:
no two electrons in the same atom can have the same four quantum numbers
43
Consequence of exclusion principle:
an atomic orbital can hold a max of two electrons, which must have opposing spins
**unique value of ms
44
A higher nuclear charge (Z) increases [...] and this lowers [...] which stabilizes the atom.
nucleus-electron attraction; sublevel energy
45
Nuclear charge stabilizes the atom and make is difficult to....
remove an electron
** harder to remove electron from Li2+ compared to H
46
Effective nuclear charge is due to...
shielding
47
Hund's rule:
when orbitals of equal energy are available, the electron configuration of lowest energy has the max number of unpaired electrons with parallel spins
48
Which electron configurations are exclusions to Aufbau's principle? What occurs? Are these still stable?
copper and chromium
to fill d sublevel, an electron from the s sublevel is taken
these are stable (low in energy)
49
Quantum number "n" represents:
principle energy level; the number matches the outermost s and p sublevels
50
Ionization generally [...] across a period and [...] down a group.
increases; decreases
51
Two exceptions to the IE trend:
1. Group 3 (B and Al) dips because they easily remove an electron to conform to a stable configuration
2. Group 6 (O and S) dips because they easily to obtain half filled orbital
52
Electron affinity:
energy release/required when an electron is added to a neural atom
53
The first electron affinities are [...].
negative
54
EA across the periodic table [...], down the periodic table [...].
increases; decreases
55
Species with unpaired electrons exhibits...
paramagnetism
56
Paramagnetism:
attracted by an external magnetic field
57
Species with all of its electrons paired exhibits...
diamagnetism
58
Diamagnetism:
not attracted (slightly repelled) by the magnetic field
59
Heisenberg's uncertainty principle:
impossible to know simultaneously the position and momentum of a particle
60
Lyman is [...] when H transmission goes to [...].
UV radiation; n=1
61
Balmer is [...] when H transmission goes to [...].
visible; n=2
62
Paschen is [...] when H transmission goes to [...].
infrared; n=3
63
Wavelength of Lyman series:
90 to 125
64
Wavelength of Balmer series:
400 to 660
65
Wavelength of Paschen series:
1200 to 1900
66
Albert Einstein contribution:
proposed that light itself is particulate, quantized into tiny "bundles" of energy
**later called photons
67
Rydberg equation:
predicts position and wavelength of any line in a given series
68
De Broglie contribution:
if energy is particle-like, perhaps matter is wavelike
69
De Broglie equation:
1. wavelength = h/(mu)
2. wavelength = h/p
* *h = planks constant
* *m = mass
* *u = speed
* *p = momentum
70
Plank:
energy is quantized
71
Bohr:
energy of atoms is quantized; photon is emitted when electron changes orbit
72
Davisson/Gemer:
electron beam is diffracted by metal crystal (helps de Broglie)
73
Compton:
photon's wavelength increases (momentum decreases) after colliding with electron
74
Einstein/de Broglie:
mass and energy are equivalent: particles have wavelength and photons have momentum (help Compton)
75
Quantum number "l" represents:
angular momentum/shape of the orbital
76
Magnetic quantum number (ml):
orientation; is the total number of orbitals in that energy level
77
If l = 0, ml will be...
0
78
If l = 1, ml will be...
-1, 0, 1
79
If l = 2, ml will be...
-2, -1, 0, 1, 2
80
If l = 3, ml will be...
-3, -2, -1, 0, 1, 2, 3
81
What does ms represent:
spin of electron (+,- 1/2)
82
Isoelectronic series:
given ions have the same number of electrons (noble gas configuration)
83
Ions without a noble gas configuration create:
1, pseudo-noble gas configuration
| 2. inert pair configuration
84
Pseudo-noble gas configuration:
empties out its highest energy level
85
Inert pair configuration:
metal atoms loses just its np electrons (stable with just ns)
86
Isoelectric series and atomic radius:
radius increases from right to left and down a period
