VSEPR Theory
Lewis Diagrams
Hybridization
IMFS
Bonding
100
What is the molecular geometry where the central atom is bonded to four other atoms with no lone pairs?
Tetrahedral
100
What are the steps to drawing a Lewis-dot structure?
1. Find the sum of valence electrons of all atoms/ions in the molecule.
2. The central atom is the least electronegative element that isn’t hydrogen. Connect the outer atoms to it by single bonds.
3. Fill the octets of the outer atoms.
4. Fill the octet of the central atom.
5. If you run out of electrons before the central atom has an octet, form multiple bonds until it does
100
What is a reliable way to find the hybridization of an atom?
Find the total number of electron domains (number of atoms bonded to it and lone pairs). If it's 4, then its sp3, 3 is sp2, 2 is sp, and if 1 the atom is most likely hydrogen.
100
All molecules experience what intermolecular force?
London Dispersion Forces
100
In a covalent bond, what determines the polarity of the bond?
The respective electronegativities of the atoms that are bonded to each other.
200
SF4 is an example of what type of molecular geometry?
See-saw
200
How many lone pairs of electrons exist on the following molecule?
BF3
A) 11 B) 10 C) 9 D) 1 E) 0
C
Boron can have a violated octet (6 e-) and each F has 3 lone pairs for a total of 9 pairs of unpaired electrons
200
If the central atom has four electron pairs, what is the hybridization?
sp3
200
Rank the IMFs in order from weakest to strongest.
Dispersion forces, Dipole-Dipole forces, hydrogen bonding, and Ion-Dipole forces
200
What is created when a polar covalent bond causes slight charges on each atom?
Dipoles
300
The O-C-O bond angle in the CO32- ion is approximately __________.
A) 120° B) 60° C) 90° D) 109.5° E) 180°
A
Because CO32- is trigonal planar in shape, the bond angle will be 120°.
300
What are some instances where the octet rule is violated?
1. Species with Odd Numbers of Electrons
2. Incomplete Octets (too few valence electrons)
3. Expanded Octets (central atom has more than eight valence electrons in a Lewis structure)
300
A carbonyl carbon is double bonded to an oxygen atom, as well as two other substituents. What type of hybrid orbitals are present on the carbonyl carbon?
sp2
300
List the IMFs found in HBr.
Dipole-Dipole forces, LDFs
300
Which of the following molecules has the shortest bond length?
A) N2 B) O2 C) Cl2 D) Br2 E) I2
A) N2
There is triple bond between N and N so it has shortest bond length compared to the other molecules
400
The F-B-F bond angle in the BF3 molecule is __________.
A) 109.5° B) 120° C) 180° D) 60° E) 90°
B
Due to the trigonal planar geometry, the F-B-F bond angle is 120°
400
Which of the following compounds contains an atom that does NOT satisfy the octet rule?
I. BCl3 II. CO2 III. NO3- IV. NO2
A) I and IV B) I, II, and IV C) IV only D) II and III
A
BCl3 has 6 electrons around boron, while NO2 only has 7 electrons around the central nitrogen.
400
What is the orbital hybridization of SF6?
sp3d2
400
As the IMFs increase, list properties of a substance that also increase.
Melting and Boiling Points, Surface Tension, Viscosity, and Heat of Vaporization
400
TRUE/FALSE: Can the bonds of a molecule be polar yet the polarity of the molecule itself be nonpolar?
TRUE
500
Why is I3- linear?
The central iodine atom is paired to two other iodine atoms with 3 lone pairs. However the lone pairs are of equatorial distance, and bonded on an axis linearly.
500
Based on formal charge considerations, which of the following would likely be the correct arrangement of atoms in nitrosyl chloride: ClNO or ClON?
CINO. The formal charges are minimized to the fullest extent; all atoms have a formal charge of zero.
500
Molecule XOp5 has a trigonal bipyramidal shape. What type of hybridization describes its bonds?
sp3d
500
The melting point of H2O(s) is 0 °C. Would you expect the melting point of H2S(s) to be −85 °C, 0 °C, or 185 °C?
−85 °C. Water has stronger hydrogen bonds so it melts at a higher temperature.
500
Exceptions to the fact that lone pairs on the central atom make a molecule polar.
Trigonal planar with three lone pairs
Octahedral with two lone pairs