Download Chapter 5 Thermochemistry 1) The internal energy of a system is

Chapter 5 Thermochemistry
1) The internal energy of a system is always increased by __________.
A) adding heat to the system
B) having the system do work on the surroundings
C) withdrawing heat from the system
D) adding heat to the system and having the system do work on the surroundings
E) a volume compression
2) Which one of the following conditions would always result in an increase in the internal energy of a system?
A) The system loses heat and does work on the surroundings.
B) The system gains heat and does work on the surroundings.
C) The system loses heat and has work done on it by the surroundings.
D) The system gains heat and has work done on it by the surroundings.
E) None of the above is correct.
3) The value of ΔE for a system that performs 111 kJ of work on its surroundings and gains 89 kJ of heat is
__________ kJ.
A) -111
B) -200
C) 200
D) -22
E) 22
4) The value of ΔE for a system that performs 13 kJ of work on its surroundings and loses 9 kJ of heat is
__________ kJ.
A) 22
B) -22
C) -4
D) 4
E) -13
5) When a system __________, ΔE is always negative.
A) absorbs heat and does work
B) gives off heat and does work
C) absorbs heat and has work done on it
D) gives off heat and has work done on it
E) none of the above is always negative.
6) Which one of the following is an exothermic process?
A) ice melting
B) water evaporating
C) boiling soup
D) condensation of water vapor
E) Ammonium thiocyanate and barium hydroxide are mixed at 25 °C: the temperature drops.
7) Which of the following is a statement of the first law of thermodynamics?
A) Ek = (1/2) mv2
B) A negative ΔH corresponds to an exothermic process.
C) ΔE = Efinal - Einitial
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D) Energy lost by the system must be gained by the surroundings.
E) 1 cal = 4.184 J (exactly)
8) A __________ ΔH corresponds to an __________ process.
A) negative, endothermic
B) negative, exothermic
C) positive, exothermic
D) zero, exothermic
E) zero, endothermic
9) A __________ ΔH corresponds to an __________ process.
A) negative, endothermic
B) positive, exothermic
C) positive, endothermic
D) zero, exothermic
E) zero, endothermic
10) ΔH for an endothermic process is __________ while ΔH for an exothermic process is __________.
A) zero, positive
B) zero, negative
C) positive, zero
D) negative, positive
E) positive, negative
11) For a given process at constant pressure, ΔH is negative. This means that the process is __________.
A) endothermic
B) equithermic
C) exothermic
D) a state function
E) energy
12) A chemical reaction that absorbs heat from the surroundings is said to be __________ and has a
__________ ΔH at constant pressure.
A) endothermic, positive
B) endothermic, negative
C) exothermic, negative
D) exothermic, positive
E) exothermic, neutral
13) A chemical reaction that releases heat to the surroundings is said to be __________ and has a __________
ΔH at constant pressure.
A) endothermic, positive
B) endothermic, negative
C) exothermic, negative
D) exothermic, positive
E) exothermic, neutral
14) The reaction
4Al (s) + 3O2 (g) → 2 Al2O3 (s)
ΔH° = -3351 kJ
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is __________, and therefore heat is __________ by the reaction.
A) endothermic, released
B) endothermic, absorbed
C) exothermic, released
D) exothermic, absorbed
E) thermoneutral, neither released nor absorbed
15) Under what condition(s) is the enthalpy change of a process equal to the amount of heat transferred into or
out of the system?
(a) temperature is constant
(b) pressure is constant
(c) volume is constant
A) a only
B) b only
C) c only
D) a and b
E) b and c
16) The units of of heat capacity are __________.
A) K/J or °C/J
B) J/K or J/°C
C) J/g-K or J/g-°C
D) J/mol
E) g-K/J or g-°C/J
17) The units of of specific heat are __________.
A) K/J or °C/J
B) J/K or J/°C
C) J/g-K or J/g-°C
D) J/mol
E) g-K/J or g-°C/J
18) A sample of calcium carbonate [CaCO3 (s)] absorbs 45.5 J of heat, upon which the temperature of the
sample increases from 21.1 °C to 28.5 °C. If the specific heat of calcium carbonate is 0.82 J/g-K, what is the
mass (in grams) of the sample?
A) 3.7
B) 5.0
C) 7.5
D) 410
E) 5.0 x 103
19) The temperature of a 12.58 g sample of calcium carbonate [CaCO3 (s)] increases from 23.6 °C to 38.2 °C.
If the specific heat of calcium carbonate is 0.82 J/g-K, how many joules of heat are absorbed?
A) 0.82
B) 5.0
C) 7.5
D) 410
E) 151
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20) An 8.29 g sample of calcium carbonate [CaCO3 (s)] absorbs 50.3 J of heat, upon which the temperature of
the sample increases from 21.1 °C to 28.5 °C. What is the specific heat of calcium carbonate?
A) .63
B) .82
C) 1.1
D) 2.2
E) 4.2
21) A 22.44 g sample of iron absorbs 180.8 J of heat, upon which the temperature of the sample increases from
21.1 °C to 39.0 °C. What is the specific heat of iron?
A) 0.140
B) 0.450
C) 0.820
D) 0.840
E) 0.900
22) For which one of the following reactions is ΔH°rxn equal to the heat of formation of the product?
A) N2 (g) + 3H2 (g) → 2NH3 (g)
B) (1/2) N2 (g) + O2 (g) → NO2 (g)
C) 6C (s) + 6H (g) → C6H6 (l)
D) P (g) + 4H (g) + Br (g) → PH4Br (l)
E) 12C (g) + 11H2 (g) + 11O (g) → C6H22O11 (g)
23) Of the following, ΔHf° is not zero for __________.
A) O2 (g)
B) C (graphite)
C) N2 (g)
D) F2 (s)
E) Cl2 (g)
24) Of the following, ΔHf° is not zero for __________.
A) Sc (g)
B) Si (s)
C) P4 (s, white)
D) Br2 (l)
E) Ca (s)
25) Consider the following two reactions:
A → 2B
A→C
ΔH°rxn = 456.7 kJ/mol
ΔH°rxn = -22.1kJ/mol
Determine the enthalpy change for the process:
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2B → C
A) -478.8 kJ/mol
B) -434.6 kJ/mol
C) 434.6 kJ/mol
D) 478.8 kJ/mol
E) More information is needed to solve the problem.
26) In the reaction below, ΔHf° is zero for __________.
Ni (s) + 2CO (g) + 2PF3 (g) → Ni(CO)2 (PF3)2 (l)
A) Ni (s)
B) CO (g)
C) PF3 (g)
D) Ni(CO)2(PF3)2 (l)
E) both CO (g) and PF3 (g)
27) For which one of the following reactions is the value of ΔH°rxn equal to ΔHf° for the product?
A) 2Ca (s) + O2 (g) → 2CaO (s)
B) C2H2 (g) + H2 (g) → C2H4 (g)
C) 2C (graphite) + O2 (g) → 2CO (g)
D) 3Mg (s) + N2 (g) → Mg3N2 (s)
E) C (diamond) + O2 (g) → CO2 (g)
28) For which one of the following reactions is the value of ΔH°rxn equal to ΔHf° for the product?
A) 2 C (s, graphite) + 2 H2 (g) → C2H4 (g)
B) N2 (g) + O2 (g) → 2 NO (g)
C) 2 H2 (g) + O2 (g) → 2 H2O (l)
D) 2 H2 (g) + O2 (g) → 2 H2O (g)
E) H2O (l) + 1/2 O2 (g) → H2O2 (l)
29) For which one of the following reactions is the value of ΔH°rxn equal to ΔH°f for the product?
A) H2O (l) + 1/2 O2 (g) → H2 O2 (l)
B) N2 (g) + O2 (g) → 2NO (g)
C) 2H2 (g) + O2 (g) → 2H2O (l)
D) 2H2 (g) + O2 (g) → 2H2O (g)
E) none of the above
30) For which one of the following reactions is the value of ΔH°rxn equal to ΔH°f for the product?
A) H2 (g) + 1/2 O2 (g) → H2O (l)
B) H2 (g) + O2 (g) → H2O2 (l)
C) 2 C (s, graphite) + 2 H2 (g) → C2H4 (g)
D) 1/2 N2 (g) + O2 (g) → NO2 (g)
E) all of the above
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31) The energy released by combustion of 1 g of a substance is called the __________ of the substance.
A) specific heat
B) fuel value
C) nutritional calorie content
D) heat capacity
E) enthalpy
32) The ΔE of a system that releases 12.4 J of heat and does 4.2 J of work on the surroundings is __________ J.
A) 16.6
B) 12.4
C) 4.2
D) -16.6
E) -8.2
33) The ΔE of a system that absorbs 12.4 J of heat and does 4.2 J of work on the surroundings is __________ J.
A) 16.6
B) 12.4
C) 4.2
D) -16.6
E) 8.2
34) The value of ΔH° for the reaction below is -72 kJ. __________ kJ of heat are released when 80.9 grams of
HBr is formed in this reaction.
H2 (g) + Br2 (g) → 2HBr (g)
A) 144
B) 72
C) 0.44
D) 36
E) -72
35) The value of ΔH° for the reaction below is -790 kJ. The enthalpy change accompanying the reaction of
0.95 g of S is __________ kJ.
2S (s) + 3O2 (g) → 2SO3 (g)
A) 23
B) -23
C) -12
D) 12
E) -790
36) The value of ΔH° for the reaction below is -1107 kJ:
2Ba (s) + O2 (g) → 2BaO (s)
How many kJ of heat are released when 5.75 g of Ba (s) reacts completely with oxygen to form BaO (s)?
A) 96.3
B) 26.3
C) 46.4
D) 23.2
E) 193
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37) The molar heat capacity of a compound with the formula C2H6SO is 88.0 J/mol-K. The specific heat of this
substance is __________ J/g-K.
A) 88.0
B) 1.13
C) 4.89
D) 6.88 ×
E) -88.0
39) Given the following reactions
Fe2O3 (s) + 3CO (s) → 2Fe (s) + 3CO2 (g)
ΔH = -28.0 kJ
3Fe (s) + 4CO2 (s) → 4CO (g) + Fe3O4 (s)
ΔH = +12.5 kJ
the enthalpy of the reaction of Fe2O3 with CO
__________ kJ.
A) -59.0
B) 40.5
C) -15.5
D) -109
E) +109
3 Fe2O3 (s) + CO (g) → CO2 (g) + 2 Fe3O4 (s)
is
40) Given the data in the table below, ΔH°rxn for the reaction 3NO2 (g) + H2O (l) → 2HNO3 (aq) + NO
(g) is __________ kJ.
A) 64
B) 140
C) -140
D) -508
E) -64
Chapter 6 Electronic Structure of Atoms
1) Which one of the following is correct?
A) ν + λ = c
B) ν ÷ λ = c
C) ν = cλ
D) λ = c ν
E) νλ = c
2) The wavelength of light emitted from a traffic light having a frequency of 5.75 × 1014 Hz is __________.
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A) 702 nm
B) 641 nm
C) 674 nm
D) 522 nm
E) 583 nm
3) Of the following, __________ radiation has the shortest wavelength.
A) X-ray
B) radio
C) microwave
D) ultraviolet
E) infrared
4) All of the orbitals in a given electron shell have the same value of the __________ quantum number.
A) principal
B) angular momentum
C) magnetic
D) spin
E) psi
5) All of the orbitals in a given subshell have the same value of the __________ quantum number.
A) principal
B) angular momentum
C) magnetic
D) A and B
E) B and C
6) Which of the subshells below do not exist due to the constraints upon the angular momentum quantum
number?
A) 4f
B) 4d
C) 4p
D) 4s
E) none of the above
7) Which one of the following is an incorrect subshell notation?
A) 4f
B) 2d
C) 3s
D) 2p
E) 3d
8) Which one of the quantum numbers does not result from the solution of the Schrodinger equation?
A) principal
B) azimuthal
C) magnetic
D) spin
E) angular momentum
9) At maximum, an f-subshell can hold __________ electrons, a d-subshell can hold __________ electrons, and
a p-subshell can hold __________ electrons.
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A) 14, 10, 6
B) 2, 8, 18
C) 14, 8, 2
D) 2, 12, 21
E) 2, 6, 10
10) If an electron has a principal quantum number (n) of 3 and an angular momentum quantum number (l) of 2,
the subshell designation is __________.
A) 3p
B) 3d
C) 4s
D) 4p
E) 4d
11) Which one of the following represents an acceptable set of quantum numbers for an electron in an atom?
(arranged as n, l, ml, and ms)
A) 2, 2, -1, -1/2
B) 1, 0, 0, 1/2
C) 3, 3, 3, 1/2
D) 5, 4,- 5, 1/2
E) 3, 3, 3, -1/2
12) Which one of the following represents an acceptable possible set of quantum numbers (in the order n, l, ml,
ms) for an electron in an atom?
A) 2, 1, -1, 1/2
B) 2, 1, 0, 0
C) 2, 2, 0, 1/2
D) 2, 0, 1, -1/2
E) 2, 0, 2, +1/2
13) Which one of the following represents an impossible set of quantum numbers for an electron in an atom?
(arranged as n, l, ml, and ms)
A) 2, 1, -1, -1/2
B) 1, 0, 0, 1/2
C) 3, 3, 3, 1/2
D) 5, 4, - 3, 1/2
E) 5, 4, -3, -1/2
14) Which electron configuration represents a violation of the Pauli exclusion principle?
A)
B)
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C)
D)
E)
15) Which electron configuration represents a violation of the Pauli exclusion principle?
A)
B)
C)
D)
E)
16) Which electron configuration represents a violation of the Pauli exclusion principle?
A)
B)
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C)
D)
E)
17) The ground state electron configuration of Fe is __________.
A) 1s22s23s23p63d6
B) 1s22s22p63s23p64s23d6
C) 1s22s22p63s23p64s2
D) 1a22s22p63s23p64s24d6
E) 1s22s23s23p10
18) The ground state electron configuration of Ga is __________.
A) 1s22s23s23p64s23d104p1
B) 1s22s22p63s23p64s24d104p1
C) 1s22s22p63s23p64s23d104p1
D) 1s22s22p63s23p64s23d104d1
E) [Ar]4s23d11
19) The ground-state electron configuration of the element __________ is [Kr]5s14d5.
A) Nb
B) Mo
C) Cr
D) Mn
E) Tc
20) The ground-state electron configuration of __________ is [Ar]4s13d5.
A) V
B) Mn
C) Fe
D) Cr
E) K
21) The ground state configuration of fluorine is __________.
A) [He]2s22p2
B) [He]2s22p3
C) [He]2s22p4
D) [He]2s22p5
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E) [He]2s22p6
22) The ground state configuration of tungsten is __________.
A) [Ar]4s23d3
B) [Xe]6s24f145d4
C) [Ne]3s1
D) [Xe]6s24f7
E) [Kr]5s24d105p5
23) The element that has a valence configuration of 4s1 is __________.
A) Li
B) Na
C) K
D) Rb
E) Cs
24) Which two elements have the same ground-state electron configuration?
A) Pd and Pt
B) Cu and Ag
C) Fe and Cu
D) Cl and Ar
E) No two elements have the same ground-state electron configuration.
25) The wavelength of light that has a frequency of 1.20 ×1013s-1 is __________ m.
A) 25.0
B) 2.50 × 10-5
C) 0.0400
D) 12.0
E) 2.5
26) The wavelength of light that has a frequency of 1.66 × 109s-1 is __________ m.
A) 0.181
B) 5.53
C) 2.00 x 10-9
D) 5.53 x 108
E) none of the above
27) Ham radio operators often broadcast on the 6-meter band. The frequency of this electromagnetic radiation
is __________ MHz.
A) 500
B) 200
C) 50
D) 20
E) 2.0
28) What is the frequency (s-1) of electromagnetic radiation that has a wavelength of 0.53 m?
A) 5.7 × 108
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B) 1.8 × 10-9
C) 1.6 × 108
D) 1.3 × 10-33
E) 1.3 × 1033
29) The energy of a photon that has a wavelength of 13.2 nm is __________ J.
A) 9.55 × 10-25
B) 1.62 × 10-17
C) 1.99 × 10-25
D) 4.42 ×
E) 1.51 × 10-17
30) What is the frequency (s-1) of a photon that has an energy of 4.38 × 10-18 J?
A) 436
B) 6.61 × 1015
C) 1.45 × 10-16
D) 2.30 × 107
E) 1.31 × 10-9
31) A mole of red photons of wavelength 725 nm has __________ kJ of energy.
A) 2.74 × 10-19
B) 4.56 × 10-46
C) 6.05 × 10-3
D) 165
E) 227
32) A mole of yellow photons of wavelength 527 nm has __________ kJ of energy.
A) 165
B) 227
C) 4.56 × 10-46
D) 6.05 × 10-3
E) 2.74 × 10-19
33) Of the following, __________ radiation has the longest wavelength and __________ radiation has the
greatest energy.
gamma
ultraviolet
visible
A) ultraviolet, gamma
B) visible, ultraviolet
C) gamma, gamma
D) visible, gamma
E) gamma, visible
34) What color of visible light has the longest wavelength?
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A) blue
B) violet
C) red
D) yellow
E) green
35) The __________ quantum number defines the shape of an orbital.
A) spin
B) magnetic
C) principal
D) angular momentum
E) psi
36) The principal quantum number of the first d subshell is __________.
A) 1
B) 2
C) 3
D) 4
E) 0
37) The electron configuration of a ground-state Ag atom is __________.
A) [Ar]4d24d9
B) [Kr]5s14d10
C) [Kr]5s23d9
D) [Ar]4s14d10
E) [Kr]5s24d10
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