Cem 83525 | Course Paper

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What is the oxidation number of each atom in sodium hydrogen carbonate, NaHCO3?

A.Na = +1, H = “1, C = +6, O = “2

B.Na = +1, H = +1, C = +4, O = “2

C.Na = +1, H = “1, C = +2, O = “2

D.Na = “1, H = +1, C = 0, O = “2

E.Na = 0, H = 0, C = 0, O = 0

Round 0.00680483 to 3 significant figures.

A.0.00

B.0.007

C.0.00680

D.0.006804

E.0.006805

Calcium carbonate, or limestone, is relatively insoluble in water. At 25 C, only 5.8 mg

will dissolve in 1.0 liter of water. What volume of water is needed to dissolve 5.0 g of

calcium carbonate?

A.4.6 10“3 L

B.3.0 10“2 L

C.1.4 102 L

D.3.4 102 L

E.8.6 102 L

Which of the following statements is/are CORRECT?

1/ Naturally occurring isotopes account for only a small fraction of known radioactive

isotopes.

2/ A few radioactive isotopes with long half-lives, such as U-235 and U-238, are found

in nature.

3/ Trace quantities of some short-lived radioactive isotopes, such as C-14, are found in

nature because they are formed continuously by nuclear reactions.

A.1 only

B.2 only

C.3 only

D.1 and 2

E.1, 2, and 3

What is the correct answer to the following expression: (205.18 ” 197.3) 6.226? Carry

out the subtraction operation first.

A.1

B.1.3

C.1.27

D.1.266

E.1.2657

Which of the following chemical equations depicts a halogenation reaction with

benzene?

A.C6H6( ) + 3 Br2(g) 3 C2H2Br2(g)

B.C6H6( ) + Cl2(g) C6H5Cl( ) + HCl(g)

C.C6H6( ) + CH3I(g) C6H5CH3( ) + HI(g)

D.C6H6( ) + Cl2(g) C6H4Cl2( ) + H2(g)

E.C6H6( ) + 3 Br2(g) 6 C6H6Br6(g)

A 50.0 mL sample of 0.155 M HNO2(aq) is titrated with 0.100 M NaOH(aq). What is

the pH of a solution after the addition of 25.0 mL of NaOH? (Ka of HNO2 = 4.5 10“4)

A.3.02

B.3.22

C.3.67

D.3.86

E.4.05

For the zero-order reaction below, a graph of ____ versus time will generate a straight

line.

A B + C rate = k[A]0

A.[A]t

C.ln[A]t

What is the O-C-N bond angle in OCN“?

A.90

B.107

C.109.5

D.120

E.180

According to the Brnsted-Lowry definition, an acid

A.increases the H3O+ concentration in an aqueous solution.

B.is a strong electrolyte.

C.is a proton acceptor.

D.increases the pH of a solution.

E.is a proton donor.

Use VSEPR theory to predict the molecular geometry of BrO3

“.

A.trigonal-pyramidal

B.trigonal-planar

C.bent

D.T-shaped

E.linear

Complete the following fusion reaction.

The nitrogen atom in cyanide ion, CN“, is surrounded by

A.one single bond and three lone pairs of electrons.

B.one double bond and one lone pair of electrons.

C.one double bond and two lone pairs of electrons.

D.one triple bond and one lone pair of electrons.

E.one triple bond and no lone pairs of electrons.

How long will it take 10.0 mL of Ne gas to effuse through a porous barrier if it has been

observed that 125 minutes are required for 10.0 mL of Ar gas to effuse through the

same barrier?

A.1.41 min.

B.31.9 min.

C.63.1 min.

D.88.8 min.

E.176 min.

Diagram 9-1

The molecular orbital diagram below may be used for the following problem(s). For

oxygen and fluorine, the s2p orbital should be lower in energy than the p2p. However,

the diagram will still yield correct bond order and magnetic behavior for these

molecules.

Energy ________ s*2p

________ ________ p*2p

________ s2p

________ ________ p2p

________ s*2s

________ s2s

________ s*1s

________ s1s

Refer to Diagram 9-1. Assuming that the molecular orbital energy diagram for a

homonuclear diatomic molecule applies to a heteronuclear diatomic molecule,

determine which of the following species is paramagnetic.

A.NO+

B.CO

C.CN“

D.OF“

E.NO

The molar nuclear mass of fluorine-19 is 18.99840 g/mol. The molar mass of a proton

is 1.007825 g/mol. The molar mass of a neutron is 1.008665 g/mol. Calculate the

binding energy (in J/mol) of F-19. (c = 2.998 108 m/s)

A.6.753 1012 J/mol

B.7.131 1012 J/mol

C.1.426 1013 J/mol

D.8.609 1014 J/mol

E.8.538 1014 J/mol

If an aqueous solution of ____ is added to a mixture of Pb2+ and Ba2+, the lead ion will

precipitate, but the barium ion will remain in solution.

A.NaOH

B.Na2SO4

C.K3PO4

D.KCO3

E.Ca(CH3CO2)2

What is the mass number of an argon atom with 22 neutrons?

A.2

B.18

C.22

D.40

E.39.95

In which of the following equilibrium systems will an increase in the pressure have no

effect on the concentrations of products and reactants?

A.H2(g) + F2(g) 2 HF(g)

B.N2(g) + 3 H2(g) 2 NH3(g)

C.CaCO3(s) CaO(s) + CO2(g)

D.2 NOBr(g) 2 NO(g) + Br2(g)

E.2 H2O(g) + O2(g) 2 H2O2(g)

Which of the following species is the strongest acid in an aqueous solution?

A.CH3CH2CO2H

B.CH2ClCO2H

C.CH3CO2H

D.CCl3CO2H

E.CHCl2CO2H

Rhodium (atomic mass 102.9 g/mol) crystallizes in a face-centered cubic unit cell. In

addition, rhodium has an atomic radius of 135 pm. What is the density (in g/cm3) of

rhodium?

A.1.53 g/cm3

B.6.14 g/cm3

C.17.4 g/cm3

D.12.3 g/cm3

E.27.8 g/cm3

What is a possible set of quantum numbers for an unpaired electron in the orbital box

diagram below?

A.n = 1, = 1, = “1, ms = +1/2

B.n = 4, = 2, = “1, ms = “1/2

C.n = 5, = 2, = “2, ms = +1/2

D.n = 5, = 0, = 0, ms = “1/2

E.n = 5, = 1, = “1, ms = +1/2

In metals, there are not enough electrons to fill all of the electronic energy levels. At 0

K, the highest energy level filled is referred to as the ________.

A.valence band

B.conduction band

C.free energy

D.Fermi level

E.band gap

Diagram 9-1

The molecular orbital diagram below may be used for the following problem(s). For

oxygen and fluorine, the s2p orbital should be lower in energy than the p2p. However,

the diagram will still yield correct bond order and magnetic behavior for these

molecules.

Energy ________ s*2p

________ ________ p*2p

________ s2p

________ ________ p2p

________ s*2s

________ s2s

________ s*1s

________ s1s

Refer to Diagram 9-1. Assume that the molecular orbital energy diagram for a

homonuclear diatomic molecule applies to a heteronuclear diatomic molecule. What is

the molecular orbital configuration of CO?

A.[core electrons] (s2s)2 (s*2s)2 (p2p)4 (s2p)2

B.[core electrons] (s2s)2 (s*2s)2 (p2p)2 (s2p)2 (p*2p)2

C.[core electrons] (s2s)2 (s*2s)2 (p2p)2 (s2p)4

D.[core electrons] (s2s)2 (s*2s)2 (p2p)6

E.[core electrons] (s2s)2 (s*2s)2 (p2p)3 (s2p)3

Which of the following chemical equations corresponds to the acid ionization constant,

Ka, for benzoic acid (C6H5CO2H)?

A.C6H5CO2

–(aq) + H3O+(aq) C6H5CO2H(aq) + H2O( )

B.C6H5CO2H(aq) + H2O( ) C6H5CO2

–(aq) + H3O+(aq)

C.C6H5CO2H(aq) + OH“(aq) C6H5CO2

–(aq) + H2O( )

D.C6H5CO2H(aq) + H3O+(aq) C6H5CO2H2

+(aq) + H2O( )

E.C6H5CO2

–(aq) + H2O( ) C6H5CO2H(aq) + OH“(aq)

Use your knowledge of group properties to predict the chemical formula for selenic

acid.

A.HSeO2

B.H2SeO3

C.H2SeO4

D.H3SeO3

E.H3SeO4

For a chemical reaction, the activation energy for the forward reaction is +181 kJ and

the activation energy for the backward reaction is +62 kJ. What is the overall energy

change for the forward reaction?

A.”119 kJ

B.”62 kJ

C.+119 kJ

D.+181 kJ

E.+243 kJ

Determine the enthalpy change for the decomposition of calcium carbonate

CaCO3(s) CaO(s) + CO2(g)

given the thermochemical equations below.

Ca(OH)2(s) CaO(s) + H2O( ) DrH = 65.2 kJ/mol-rxn

Ca(OH)2(s) + CO2(g) CaCO3(s) + H2O( ) DrH = -113.8 kJ/mol-rxn

C(s) + O2(g) CO2(g) DrH = -393.5 kJ/mol-rxn

2 Ca(s) + O2(g) 2 CaO(s) DrH = -1270.2 kJ/mol-rxn

A.+48.6 kJ/mol-rxn

B.+179.0 kJ/mol-rxn

C.+345.5 kJ/mol-rxn

D.+441.0 kJ/mol-rxn

E.+1711.7 kJ/mol-rxn

Use the standard reduction potentials below to determine which element or ion is the

best oxidizing agent.

O2(g) + 4 H+(aq) + 4 e“ 2 H2O( ) E = +1.229 V

Hg2

2+(aq) + 2 e“ 2 Hg( ) E = +0.789 V

I2(s) + 2 e“ 2 I“(aq) E = +0.535 V

A.I2(s)

B.O2(g)

C.I“(aq)

D.Hg2

2+(aq)

E.H2O( )

If a cordless phone operates at a frequency of 9.00 108 s“1. What is the wavelength of

this radiation?

A.0.333 m

B.1.99 10“25 m

C.3.33 10“9 m

D.3.71 10“18 m

E.2.70 1017 m

Which element from the first transition series does NOT react with hydrochloric acid?

A.titanium

B.chromium

C.cobalt

D.nickel

E.copper