QUESTIONS AND CORRECT ANSWERS 2024
ALREADY GRADED A+|NEWLY UPDATE
*An incorrect Lewis structure for the iodate anion, IO3- (depicted below) would include one lone pair of
electrons on the central iodine atom, one double bond to an oxygen atom (double bond oxygen is
labeled O2 below) and two single bonds to the other oxygen atoms (single bond oxygens are labeled O1
and O3). What are the formal charges for this incorrect Lewis structure for the iodate anion? Note that
the lone pairs for the oxygen atoms are not shown. O2 atom= 0; O1 and O3 atoms -1; I atoms +1
*I stated that the above Lewis structure of iodate is incorrect. Identify the problem (s) with this lewis
structure. Iodine should further expand its octet to remove formal charge.
*As the number of bonds between two carbon atoms increases, which one of the following decreases?
Bond length
Which of the following is NOT correct?
a.FeCl2 is named iron (II) chloride
b. Al2(CO3)3 is the formula for aluminum carbonate
c. (NH4)2NO2 is the formula for ammonium nitrite
d. MgSO4 is named magnesium sulfate
e. Ni(OH)2 is the formula for nickel (II) hydroxide (NH4)2NO2 is the formula for ammonium nitrite
*The equation H+ + OH- --> H2O represents the net ionic equation for the reaction of Hydrobromic
acid with potassium hydroxide
*Which of the following elements is most likely to form a molecular structure that disobeys the octet
rule?
P
C
N
O
F P
,A mixture of BaCl2 and NaCl is analyzed by precipitating all the barium as BaSO4. After addition of an
excess of Na2SO4 to a 3.831- g sample of the mixture, the mass of precipitate collected is 2.826 g. What
is the mass percentage of barium chloride in the mixture?
a. 82.50 %
b. 73.77 %
c. 43.39 %
d. 65.80 %
e. 13.61 % 65.80%
*Hydrogen peroxide decomposes into oxygen and water. What mass of oxygen is formed from the
decomposition of 125 g of H2O2?
a. 58.8 g
b. 66.4 g
c. 107 g
d. 118 g
e. 125 g 58.8 g
What are the spectator ions in the reaction between aqueous hydrochloric acid and ammonia?
a. H+ only
b. Cl- only
c. H+ and NH4+
d. Cl- and NH4+
e. H+, Cl-, and NH4+ Cl- only
*Chemical analysis has determined that a compound has an empirical formula of CH2. If the molar mass
is 56 g/mol what is the molecular formula?
a. C3H20
b. C4H8
c. C4H2
, d. C2H4
e. C5H10 C4H8
The complete combustion go 0.20 moles of propane, C3H8, will consume 1.0 mol O2 and produce 0.60
mol CO2.
*When 3.5 g of magnesium metal is burned, 3.9 g of MgO is produced. What is the percent yield of
MgO? 67%
Use VSPER theory to predict the electron domain geometry of bromine trifluoride, BrF3 Trigonal
bipyramidal
*Use VSPER theory to predict the molecular geometry of BrF5. Square pyramidal
Identify the incorrect statement regarding the molecule NF2Cl There is only one lone pair of electrons
*Place the following molecules in order from smallest to largest H-N-H bond angles: NH4+, NH3, and
NH2- NH2-< NH3 < NH4+
Assuming there is a difference in electronegativity between the central and peripheral atoms, which of
the following geometries is not symmetric and therefore MUST result in a polar molecule? Square
pyramidal
Under certain conditions, the reaction of ammonia with oxygen will produce a 52% yield of NO. What
mass of oxygen must react with excess ammonia to yield 11.7 g NO?
4NH3 + 5O2 --> 4NO + 6H2O 30.0 g
Refer to the diagram above. For which of the following diatomic molecules would the bond order
become greater if an electron is removed (i.e., if the molecule is converted to the positive ion in its
ground state)?
B2
C2
P2
F2
Na2 F2
Refer to the diagram above. According to molecular orbital theory, which of the following species is
least likely to exist (i.e., has the lowest bond order)?
(H2)2-