CEM 26943 | Course Paper

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Use the following thermodynamic data.

Species DfH (kJ/mol) S (J/Kmol)

Fe(s) 0.0 27.8

O2(g) 0.0 205.1

Fe3O4(s) “1118.4 146.4

to calculate DS (universe) for the formation of Fe2O3(s) at 298.15 K.

3 Fe(s) + 2 O2(g) Fe3O4(s)

A.”3404 J/K

B.”1162 J/K

C.+561.2 J/K

D.+3404 J/K

E.+7639 J/K

Mount Everest rises to a height of 8.850 103 m above sea level. At this height, the

atmospheric pressure is 231 mm Hg. At what temperature (in C) does water boil at the

summit of Mount Everest? The vapor pressure of water at 373 K is 760.0 mm Hg.

(DvapH for H2O = 40.7 kJ/mol and R = 8.314 J/Kmol)

A.4.07 C

B.69.0 C

C.72 C

D.87 C

E.364 C

Which of the following characteristics apply to NCl3?

1/ polar bonds

2/ nonpolar molecule

3/ triangular-planar molecular shape

4/ sp2 hybridized

A.1 only

B.1 and 2

C.3 and 4

D.1, 2, and 3

E.1, 2, 3, and 4

When an aldehyde is oxidized, the product is a(n) ____.

A.ester

B.ketone

C.ether

D.alcohol

E.carboxylic acid

If 4.49 g NaNO3 is dissolved in enough water to make 250.0 mL of solution, what is the

molarity of the sodium nitrate solution?

A.1.80 10“2 M

B.5.28 10“2 M

C.2.11 10“1 M

D.1.32 10“2 M

E.18.0 M

Ethanol has an enthalpy of vaporization of 42.3 kJ/mol. The compound has a vapor

pressure of 1.00 atm at 78.3 C. At what temperature is the vapor pressure equal to 0.800

atm? (R = 8.314 J/Kmol)

A.”83.8 C

B.”24.4 C

C.62.6 C

D.73.0 C

E.78.0 C

A chemical reaction in a bomb calorimeter evolves 3.86 kJ of energy in the form of

heat. If the temperature of the bomb calorimeter increases by 4.17 K, what is the heat

capacity of the calorimeter?

A.3.87 103 J/K

B.311 J/K

C.926 J/K

D.1.8 103 J/K

E.1.61 104 J/K

If a metal crystallizes in a primitive cubic lattice, each metal atom has ____ “nearest

neighbors.”

A.3

B.4

C.6

D.8

E.12

Assume that the following endothermic chemical reaction is at equilibrium.

C(s) + H2O(g) H2(g) + CO(g)

Which of the following statements is/are CORRECT?

1/ Increasing the concentration of H2(g) will cause the reaction to proceed in the

backward direction, increasing the equilibrium concentration of H2O(g).

2/ Decreasing the temperature will cause the reaction to proceed in the forward

direction, increasing the equilibrium concentration of CO(g).

3/ Increasing the amount of C(s) will cause the reaction to proceed in the forward

direction, increasing the equilibrium concentration of CO(g).

A.1 only

B.2 only

C.3 only

D.1 and 2

E.1, 2, and 3

Consider the following half-reactions:

Ag+(aq) + e“ Ag(s) E = +0.80 V

Cu2+(aq) + 2 e“ Cu(s) E = +0.34 V

Pb2+(aq) + 2 e“ Pb(s) E = “0.13 V

Fe2+(aq) + 2 e“ Fe(s) E = “0.44 V

Al3+(aq) + 3 e“ Al(s) E = “1.66 V

Which of the above metals or metal ions will oxidize Pb(s)?

A.Ag+(aq) and Cu2+(aq)

B.Ag(s) and Cu(s)

C.Fe2+(aq) and Al3+(aq)

D.Fe(s) and Al(s)

E.Cu2+(aq) and Fe2+(aq)

What intermolecular force or bond is primarily responsible for the solubility of carbon

dioxide (CO2) in water?

A.dipole/dipole force

B.hydrogen bonding

C.dipole/induced dipole force

D.hydrogen bonding-dipole force

E.ion-induced dipole force

If DrG for the following reaction is “22.2 kJ/mol-rxn, calculate .

Cu2+(aq) + 2 Ag(s) + 2 Cl“(aq) Cu(s) + 2 AgCl(s)

A.”0.460 V

B.”0.115 V

C.+0.115 V

D.+0.230 V

E.+0.559 V

According to the Bohr model for the hydrogen atom, the energy necessary to excite an

electron from n = 1 to n = 2 is ____ the energy necessary to excite an electron from n =

2 to n = 3.

A.less than

B.greater than

C.equal to

D.either equal to or greater than

E.either less than or equal to

What is the correct name for CCl4?

A.carbon chlorine

B.tetracarbon chloride

C.carbon tetrachloride

D.carbon(IV) chloride

E.tetrachlorocarbide

How many nutritional calories are equivalent to 1150 kJ?

A.0.10 Cal

B.1.15 Cal

C.275 Cal

D.4.8 103 Cal

E.3.6 10-3 Cal

What shell contains a total of 9 orbitals?

A.n = 2

B.n = 3

C.n = 4

D.n = 5

E.n = 9

A barometer is filled with a cylindrical column of mercury that is 76.0 cm high and

1.000 cm in diameter. If the density of mercury is 13.53 g/cm3, what is the mass of

mercury in the column? (Volume = pr2h)

A.0.227 g

B.4.41 g

C.808 g

D.1.03 103 g

E.3.23 103 g

Avogadro’s hypothesis states that equal volumes of gases under the same conditions of

temperature and pressure have equal ____.

A.numbers of particles

B.particle velocities

C.molar masses

D.densities

E.masses

Which of the following statements is/are CORRECT?

1/ If a reaction occurs at constant pressure, q = DH.

2/ The change in energy for a system is defined as the sum of the energies transferred as

heat and work (i.e., DU = q + w).

3/ If a reaction occurs at constant volume, q = w

A.1 only

B.2 only

C.3 only

D.1 and 2

E.1, 2, and 3

What is the hybridization of a central atom that has four sigma bonds and has no lone

pairs of electrons?

A.sp

B.sp2

C.sp3

D.sp3d

E.sp3d2

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. According to molecular orbital theory, what is the bond order of

A.1

B.3/2

C.2

D.5/2

E.3

Which of the following conditions is/are met at the equivalence point of the titration of

a monoprotic weak base with a strong acid?

1/ The moles of acid added from the buret equals the initial moles of weak base.

2/ The volume of acid added from the buret must equal the volume of base titrated.

3/ The pH of the solution is less than 7.00.

A.1 only

B.2 only

C.3 only

D.1 and 3

E.2 and 3

The speed of light in a vacuum is 3.00 108 m/s. What is the speed of light in units of

kilometers per hour?

A.1.20 10“2 km/hr

B.8.33 101 km/hr

C.8.33 107 km/hr

D.1.08 109 km/hr

E.1.08 1015 km/hr

An unsaturated hydrocarbon is

A.a hydrocarbon that contains oxygen.

B.a compound in which all carbon atoms have four single bonds.

C.a compound in which one or more carbon atoms have double or triple bonds.

D.a hydrocarbon that is dissolved in water.

E.a cycloalkane with five or more carbons.

Which equation depicts aqueous hydrogen sulfide, behaving as a Brnsted-Lowry acid in

water?

A.H2S(aq) + 2 OH“(aq) SO2(aq) + 2 H2(g)

B.H2S(aq) + H3O+(aq) H3S+(aq) + H2O( )

C.H2S(aq) + H2O( ) HS“(aq) + H3O+(aq)

D.HS“(aq) + H3O+(aq) H2S(aq) + H2O( )

E.HS“(aq) + H2O( ) HSO+(aq) + H2(s)

Identify the product(s) of the hydrogenation of cis-2-hexene.

A.2-hydroxyhexane

B.2,3-dihydroxyhexane

C.trans-2-hexane

D.carbon dioxide and water

E.hexane

Specific heat capacity is

A.the quantity of heat needed to change the temperature of 1.00 g of a substance by 1

B.the quantity of heat needed to change the temperature of 1.00 g of a substance by

4.184 K.

C.the capacity of a substance to gain or lose a 1.00 J of energy in the form of heat.

D.the temperature change undergone when 1.00 g of a substance absorbs 4.184 J.

E.the maximum amount of energy in the form of heat that 1.00 g of a substance may

absorb without decomposing.

What is the correct name for Ca(CH3CO2)2?

A.calcium(II) carbonate

B.calcium carbonate

C.calcium acetate

D.acetic calcide

E.calcium carbonide

Write a balanced chemical equation for the reaction of potassium and water.

A.K(s) + H2O( ) KO(s) + H2(g)

B.2 K(s) + 2 H2O( ) 2 KOH(aq) + H2(g)

C.2 K(s) + 2 H2O( ) K2O2(s) + 2 H2(g)

D.2 K(s) + H2O( ) K2O(s) + H2(g)

E.4 K(s) + 2 H2O( ) 4 KH(s) + O2(g)

For a hydrogen atom, calculate the wavelength of an emitted photon in the Lyman

series that results from the transition n = 3 to n = 1. The Rydberg constant is 1.097 107

m“1. (h = 6.626 10“34 Js and c = 2.998 108 m/s)

A.102.6 nm

B.95.0 nm

C.91.2 nm

D.434.1 nm

E.1005 nm

If the density of nitrogen in air is 0.87 g/L, what mass (in kg) of nitrogen is contained in

a room with dimensions of 4.0 m 3.5 m 2.4 m?

A.29 kg

B.39 kg

C.2.6 10“2 kg

D.2.9 104 kg

E.26 kg

The Ksp of BaSO4 is 1.1 10“10 at 25 C. What mass of BaSO4 (molar mass = 233.4

g/mol) will dissolve in 1.0 L of water at 25 C?

A.2.6 10-8 g

B.4.5 10-8 g

C.1.0 10-5 g

D.1.6 10-4 g

E.2.4 10-3 g

Internal energy and enthalpy are state functions. What is meant by this statement?

Which of the following statements is/are CORRECT?

1. A hydrogen atom with 1 proton and zero neutrons is assigned a mass of exactly

1 atoms mass unit.

2. 1 atomic mass unit is equivalent to 9.11 x 10-28 g.

3. A carbon atom with 6 protons and 6 neutrons is assigned a mass of exactly 12

atomic mass units.

A. 1 only

B. 2 only

C. 3 only

D. 1 and 2

E. 1, 2, and 3

The gas constant, R, expressed in SI units has a value of 8.314. The units of the constant

are ________.

Explain the function of a salt bridge in a voltaic cell.

Technetium-99m is routinely used in medical imaging. The italics m means the nucleus

is ________.

Iodine trifluoride, IF3, has a trigonal-bipyramidal electron-pair geometry and a t-shaped

molecular geometry. The hybridization of the central iodine atom is ________.

When a secondary battery provides electrical energy, it is acting as a voltaic cell. When

the battery is recharging, it is operating as a(n) ________ cell.

Why are you at greater risk from being burned by steam at 100 C than from liquid water

at the same temperature?

What evidence does the photoelectric effect provide that photons are not only waves?

The complex ion [NiCl4]2″ is paramagnetic, but the complex ion [Ni(NH3)4]2+ is

diamagnetic. Why do the magnetic properties of these two nickel complexes differ?

Neutron ________ analysis is a non-destructive process in which a sample is irradiated

with neutrons. The neutrons react with nuclei to form isotopes with masses one unit

higher than the original nuclei. The nuclei are formed in excited states and they emit

gamma radiation that can be used to both identify the presence of an element and

quantify how much is present.

A molecule that can behave as either a Brnsted-Lowry acid or base is termed ________.

What is the difference between the accuracy of measurements and the precision of

measurements?

The Bohr model predicts that the energy of an atom’s electron is ________, meaning

that the electron can only occupy orbitals of specific energies.

If a molecule has a positive and negative end, the molecule is said to have a(n)

________ moment.

The total entropy of the universe is always increasing. This is a statement of the

________ law of thermodynamics.

Termolecular elementary steps are rare. Why?

When a Lewis acid combines with a Lewis base, the base supplies both electrons to the

bond. This type of chemical bond is called a(n) ________ covalent bond.

EDTA4″, a hexadentate ligand, is most effective at chelating metal ions when the pH is

greater than 12. Explain why low pH decreases the chelating ability of the ligand.