5) How many of the following molecules have sp3d2 hybridization on the central atom?
SeCl6 XeCl4 IF5 AsCl5
1
3
0
2
4
Answer: B
6) Which of the following would you expect to have no net dipole moment?
CHF3
NF3
CH2F2
+
+ Answer: D. The reason is that the pulls on the F atoms and H atoms cancel eachother out diagonally. In E, the pull on top is stronger than the pull on bottom
7) Describe a sigma bond
Side by side overlap of d orbitals
end to end overlap of p orbitals
s orbital overlapping with the side of a p orbital
overlap of two d orbitals
p orbital overlapping with an f orbital
Answer: B
8) Assume the Molecular Orbital diagram for a homonuclear diatomic molecule applies to CN^-. Which of the following is true:
The molecule is diamagnetic and has a bond order of 3
The molecule is paramagnetic and has a bond order of 3
The molecule is paramagnetic and has a bond order of 2.5
The molecule is diamagnetic and has a bond order of 2.5
The moldecule is paramagnetic and has a bond order of 3.5
Answer: A. A molecule is only paramagnetic if it has 6 or twelve valence electrons.
9) Dinitrogen monoxide gas decomposes to form nitrogen gas and oxygen gas. How many grams of oxygen are formed when 20.0 g of dinitrogen monoxide decomposes?
0.138 g
7.27 g
14.5 g
29.1 g
Answer: B.
10) Give the net ionic equation for the reaction (if any) that occurs when aqueous solutions of Na2CO3 and HCl are mixed
ll) Based on the balanced chemical equation shown below, determine the molarity of a solution containing Fe2+(aq), if 40.00 mL of the Fe2+(aq) solution is required to completely read With 30.00 mL of a 0.125 M potassium bromate, KBrO3(aq), solution. The chemical equatlon for the reaction is
12) Which of the following signs on q and w represent a system on which the surroundings are doing work, as well as losing heat to the surroundings?
q = +, w = -
q = -, w = +
q = +, w = +
q = -, w = -
None of these represent the system referenced above
Answer: B
13) Based on the balanced chemical equation shown below, what volume of 0.250 M K2S2O3(aq), is needed to completely react with 12.44 mL of 0.125 M KI3(aq), according to the following chemical equation.
3.11 mL
6.22 mL
12.4 mL
49.8 mL
Answer: C
14) Choose the statement below that is true.
A weak acid solution consists of mostly nonionized acid molecules.
The term “strong electrolyte” means that the substance is extremely reactive.
A strong acid solution consists of only partially ionized acid molecules.
The term “weak electrolyte” means that the substance is inert.
A molecular compound that does not ionize in solution is considered a strong electrolyte.
Answer: A
15) Automotive air bags inflate when sodium azide decomposes explosively to its constituent elements
How many grams of sdium azide are required to produce 25.0g of nitrogen?
1.34
0.595
58.0
38.7
87.0
Answer: D
16) Draw the Lewis structure for the molecule CH3CH2CCH. How many sigma and pi bonds does it contain?
11 sigma, 0 pi
9 sigma, 1 pi
8 sigma, 3 pi
9 sigma, 2 pi
8 sigma, 1 pi
Answer: D
17) The hybrid orbital set used by the central atom in O3 is
sp
sp2
sp3
sp3d
sp3d2
Answer: B. The steric number on the central atom is 3 so sp2
18) A molecule containing a central atom with sp3 hybridization has a(n) __ electron geometry.
linear
trigonal bipyramidal
octahedral
tetrahedral
bent
Answer: D
19) Draw the appropriate molecular orbital diagram to determine which of the following is most stable.
C2^2+
N2^2+
B2
C2^2-
B2^2+
Answer: D/span>
20) If the percent yield for the following reaction is 75.0%, and 25.0 g of NO2 are consumed in the reaction, how many grams of nitric acid, HNO3(aq) are produced?
3 NO2 (g) + H2O(l) -> 2 HNO3 (aq) + NO(g)
17.1 g
22.8 g
30.4 g
38.5 g
Answer: A
21) Determine the molarity of a solution formed by dissolving 468 mg of MgI2 in enough water to yield 50.0 mL of solution
0.0297 M
0.0337 M
0.0936 M
0.0107 M
0.0651 M
Answer: B
22) Determine the name for aqueous HBr.
bromic acid
bromous acid
hydrobromous acid
hydrogen bromate
hydrobromic acid
Answer: E
23) Which of the following compounds is soluble in water?
Ca3(PO4)2
HgS
Ni(NO3)2
MgCO3
Answer: C
24) How many milliliters of a 0.266 M CSNO3 solution are required to make 150.0 mL of 0.075 M CSNO3 solution?
53.2 mL
42.3 mL
18.8 mL
23.6 mL
35.1 mL
Answer: B
25) Lithium and nitrogen react in a combination reaction to produce lithium nitride:
6 Li(s) + N2(g) -> 2LiN(s)
In a particular experiment, 1.00-g samples of each reagent are reacted. The theoretical yield of lithium nitride is __ g.
1.01
0.84
5.0
1.67
2.50
Answer: D
26) Strontium phosphate reacts with sulfuric acid to form strontium sulfate and phosphoric acid. What is the coefficient for sulfuric acid when the equation is balanced using the lowest, whole-numbered coefficients?
1
2
3
None of these
Answer: C
Consider the molecule below. Determine the hybridization at each of the 3 labeled atoms
