For this reaction at 25 °C, DG°f is -16.5 kJ
mol¯1. What is the equilibrium constant, Keq, for this reaction at
(B) 7.80 x 102
(C) 4.57 x 106
(D) 2.98 x 1034
22. What are the signs for DH, DS,
and DG for the freezing of liquid water at -10 °C?
23. Which of these factors affect the value of the specific rate constant for the
reaction 2A(g) ---> B(g)?
(A) I, II, and III
(B) I and II only
(C) II and III only
(D) III only
24. Which statement about work and heat is true?
(A) A given quantity of heat can be completely converted to work.
(B) Heat and work are both state functions.
(C) Some heat is always produced when work is done.
(D) Work is a state function, whereas heat is not.
25. The reaction between KMnO4 and H2C2O4
can be followed by monitoring the disappearance of the purple color of the MnO4¯
ion. These data were obtained for the reaction carried out at a constant temperature of 25
of MnO4¯ (aq), M s¯1
1.08 x 10¯2 M
5.4 x 10¯5
1.08 x 10¯2 M
1.1 x 10¯4
2.17 x 10¯2 M
2.1 x 10¯4
Specify the order of this reaction with respect to [MnO4¯]
26. For which reaction order is the half-life independent of the initial concentration?
I first order
II second order
(A) I only
(B) II only
(C) both I and II
(D) neither I nor II
27. What is the activation energy for the reverse of this reaction?
N2O4(g) ---> 2NO2(g)
Data for the given reaction is: DH = + 54.0 kJ and Ea
= +57.2 kJ.
36. The equilibrium constant for this reaction is 3.6 x 10¯7
OCl¯(aq) + H2O(l) <===> HOCl(aq) + OH¯(aq)
What is Ka for HOCl?
(A) 2.8 x 10¯8
(B) 3.6 x 10¯7
(C) 6.0 x 10¯4
(D) 2.8 x 106
37. For which titration would the use of phenophthalein introduce a significant error?
Kindicator for phenolphthalein = 1 x 10¯9
38. When solid lead iodide is added to water, the equilibrium concentration of I¯
becomes 2.6 x 10¯3 M. What is the Ksp for PbI2?
(A) 2.2 x 10¯9
(B) 8.8 x10¯9
(C) 1.8 x 10¯8
(D) 3.5 x 10¯8
39. When these standard half reactions are combined to give a
spontaneous reaction in a voltaic cell, what is the cell voltage?
Standard Reduction Potentials,
Sn2+(aq) + 2e¯ ---> Sn(s)
Ag+(aq) + e¯ ---> Ag(s)
(A) 1.74 V
(B) 1.46 V
(C) 0.94 V
(D) 0.66 V
40. How many moles of elections are transferred when this equation is balanced with the
smallest whole number coefficients?
_IO3¯ + _H2O2 + _H+ --->
_I2 + _O2 + _H2O
41. If the E°cell for a given reaction has a negative value, which gives
the correct relationships for the values of DG° and Keq?
A. DG° > 0; Keq < 1
B. DG° > 0; Keq > 1
C. DG° < 0; Keq > 1
D. DG° < 0; Keq < 1
42. When anions undergo oxidation, they move toward the
A. anode of a voltaic cell and the cathode of an electrolytic cell
B. cathode of a voltaic cell and the anode of an electrolytic cell
C. anodes of both types of cells
D. cathodes of both types of cells
43. How much time is required to produce 0.10 mol of chlorine gas during the
electrolysis of molten sodium chloride using a current of 3.0 amps?
A. 55 min
B. 110 min
C. 220 min
D. 330 min
44. The visible spectrum of the hydrogen atom consists of a series of lines that
A. converge at low energies.
B. converge at high energies.
C. are separated by equal energies.
D. are randomly spaced.
45. When the elements C, N and Si are arranged in order of increasing first ionization
energy, which is the correct order?
A. C < N < Si
B. N < C < Si
C. Si < C < N
D. Si < N < C
46. Which is a possible set of quantum numbers for a valence electron in ground state
atom of phosphorus?
47. These are the first eight ionization energies for a particular
neutral atom. All values are expressed in MJ mol¯1. How many valence electrons
does this atom possess?
48. Which gaseous ion in its ground state has the greatest number of unpaired
49. Which of these characteristics describe the PCl3 molecule?
I trigonal planar shape
II sp3 hybridized phosphorus atom
III polar bonds
IV nonpolar molecule
A. I and II only
B. II and III only
C. I and IV only
D. I, III, and IV only
50. According to the Lewis structure for the HNNH, how many sigma bonds, pi bonds, and
lone pairs of electrons are present?
lone pairs of electrons
51. In the Lewis structure for the BrF4¯ ion, how many lone pairs of
electrons are placed around the central atom?
52. What term is used for the measure of an atom's attraction for the electrons that
constitute a covalent bond?
(A) ionization energy
(B) bond dissociation energy
(C) electron affinity
53. One way of writing the Lewis structure of the cyanate ion, OCN¯, places one double
bond between the carbon atom and the oxygen atom and another double bond between the
carbon atom and the nitrogen atom. What are the formal charges on the oxygen, carbon, and
nitrogen atoms, respectively for this structure?