Deck 6: Thermochemistry

Question 1

Define energy.

A) the flow of energy caused by a chemical reaction
B) the flow of energy caused by a temperature difference
C) the result of a force acting through a distance
D) the capacity to do work
E) a chemical reaction

Answer 1

the capacity to do work

Question 2

Define work.

A) the flow of energy caused by a chemical reaction
B) the flow of energy caused by a temperature difference
C) the result of a force acting through a distance
D) the capacity to do work
E) a chemical reaction

Answer 2

the result of a force acting through a distance

Question 3

Determine the final temperature of a gold nugget (mass = 376 g)that starts at 398 K and loses 4.85 kJ of heat to a snowbank when it is lost.The specific heat capacity of gold is 0.128 J/g°C.

A) 133 K
B) 398 K
C) 187 K
D) 297 K
E) 377 K

Answer 3

297 K

Question 4

Calculate the change in internal energy (ΔE)for a system that is giving off 25.0 kJ of heat and is changing from 12.00 L to 6.00 L in volume at 1.50 atm pressure.(Remember that 101.3 J = 1 L^∙atm)

A) +25.9 kJ
B) -16.0 kJ
C) -25.9 kJ
D) -24.1 kJ
E) 937 kJ

Question 5

Energy that is associated with the relative positions of electrons and nuclei in atoms and molecules is called

A) kinetic energy.
B) thermal energy.
C) potential energy.
D) chemical energy.

Question 6

Energy that is associated with the temperature of an object is called

A) kinetic energy.
B) thermal energy.
C) potential energy.
D) chemical energy.

Question 7

Energy that is associated with the motion of an object is called

A) kinetic energy.
B) thermal energy.
C) potential energy.
D) chemical energy.

Question 8

Which of the following signs on q and w represent a system that is doing work on the surroundings,as well as gaining heat from the surroundings?

A) q = +, w = -
B) q = -, w = +
C) q = +, w = +
D) q = -, w = -
E) None of these represent the system referenced above.

Question 9

For ΔE_sys to always be -,what must be TRUE?

A) q = w
B) +q > -w
C) +w > -q
D) -w > +q

Question 10

Which of the following signs on q and w represent the surroundings that is doing work on the system,as well as losing heat to the surroundings?

A) q = +, w = -
B) q = -, w = +
C) q = +, w = +
D) q = -, w = -
E) None of these represent the system referenced above.

Question 11

A 21.8 g sample of ethanol (C₂H₅OH)is burned in a bomb calorimeter,according to the following reaction.If the temperature rises from 25.0 to 62.3°C,determine the heat capacity of the calorimeter.The molar mass of ethanol is 46.07 g/mol. C₂H₅OH(l)+ 3 O₂(g)→ 2 CO₂(g)+ 3 H₂O(g)ΔH°_rxn = -1235 kJ

A) 4.99 kJ/°C
B) 5.65 kJ/°C
C) 63.7 kJ/°C
D) 33.1 kJ/°C
E) 15.7 kJ/°C

Question 12

The law of ________ states that energy that can be neither created nor destroyed.

A) kinetic energy
B) the consecration of energy
C) potential energy
D) the conservation of energy
E) thermochemistry

Question 13

A 4.98 g sample of aniline (C₆H₅NH₂,molar mass = 93.13 g/mol)was combusted in a bomb calorimeter with a heat capacity of 4.25 kJ/°C.If the temperature rose from 29.5°C to 69.8°C,determine the value of ΔH°_comb for aniline.

A) +7.81 × 10³ kJ/mol
B) -3.20 × 10³ kJ/mol
C) +1.71 × 10³ kJ/mol
D) -1.71 × 10³ kJ/mol
E) -7.81 × 10³ kJ/mol

Question 14

Define heat.

A) the flow of energy caused by a chemical reaction
B) the flow of energy caused by a temperature difference
C) the result of a force acting through a distance
D) the capacity to do work
E) a chemical reaction

Question 15

A 6.55 g sample of aniline (C₆H₅NH₂,molar mass = 93.13 g/mol)was combusted in a bomb calorimeter.If the temperature rose by 32.9°C,use the information below to determine the heat capacity of the calorimeter. 4 C₆H₅NH₂(l)+ 35 O₂(g)→ 24 CO₂(g)+ 14 H₂O(g)+ 4 NO₂(g)
ΔH°_rxn = -1.28 × 10⁴ kJ

A) 97.3 kJ/°C
B) 38.9 kJ/°C
C) 5.94 kJ/°C
D) 6.84 kJ/°C
E) 12.8 kJ/°C

Question 16

Which of the following signs on q and w represent the surroundings that is doing work on the system,as well as gaining heat from the surroundings?

A) q = +, w = -
B) q = -, w = +
C) q = +, w = +
D) q = -, w = -
E) None of these represent the system referenced above.

Question 17

The temperature rises from 25.00°C to 29.00°C in a bomb calorimeter when 3.50 g of sucrose undergoes combustion in a bomb calorimeter.Calculate ΔE_rxn for the combustion of sucrose in kJ/mol sucrose.The heat capacity of the calorimeter is 4.90 kJ/°C.The molar mass of sugar is 342.3 g/mol.

A) -1.92 × 10³ kJ/mole
B) 1.92 × 10³ kJ/mole
C) -1.23 × 10³ kJ/mole
D) 2.35 × 10⁴ kJ/mole

Question 18

Energy that is associated with the position or composition of an object is called

A) kinetic energy.
B) thermal energy.
C) potential energy.
D) chemical energy.

Question 19

A 12.8 g sample of ethanol (C₂H₅OH)is burned in a bomb calorimeter with a heat capacity of 5.65 kJ/°C.Using the information below,determine the final temperature of the calorimeter if the initial temperature is 25.0°C.The molar mass of ethanol is 46.07 g/mol. C₂H₅OH(l)+ 3 O₂(g)→ 2 CO₂(g)+ 3 H₂O(g)ΔH°_rxn = -1235 kJ

A) 53.4°C
B) 28.1°C
C) 111°C
D) 85.7°C
E) 74.2°C

Question 20

Which of the following signs on q and w represent a system that is doing work on the surroundings,as well as losing heat to the surroundings?

A) q = -, w = -
B) q = +, w = +
C) q = -, w = +
D) q = +, w = -
E) None of these represent the system referenced above.

Question 21

A 6.55 g sample of aniline (C₆H₅NH₂,molar mass = 93.13 g/mol)was combusted in a bomb calorimeter with a heat capacity of 14.25 kJ/°C.If the initial temperature was 32.9°C,use the information below to determine the value of the final temperature of the calorimeter. 4 C₆H₅NH₂(l)+ 35 O₂(g)→ 24 CO₂(g)+ 14 H₂O(g)+ 4 NO₂(g)
ΔH°_rxn = -1.28 × 10⁴ kJ

A) 257°C
B) 46.6°C
C) 48.7°C
D) 41.9°C
E) 931°C

Question 22

According to the following reaction,how much energy is evolved during the reaction of 2.50 L B₂H₆ and 5.65 L Cl₂? (Both gases are initially at STP.)The molar mass of B₂H₆ is 27.67 g/mol. B₂H₆(g)+ 6 Cl₂(g)→ 2 BCl₃(g)+ 6 HCl(g)ΔH°_rxn = -1396 kJ

A) 58.7 kJ
B) 156 kJ
C) 215 kJ
D) 352 kJ
E) 508 kJ

Question 23

An endothermic reaction has

A) a negative ΔH, absorbs heat from the surroundings, and feels cold to the touch.
B) a positive ΔH, gives off heat to the surroundings, and feels warm to the touch.
C) a negative ΔH, gives off heat to the surroundings, and feels warm to the touch.
D) a positive ΔH, absorbs heat from the surroundings, and feels cold to the touch.
E) a positive ΔH, absorbs heat from the surroundings, and feels warm to the touch.

Question 24

A student is preparing to perform a series of calorimetry experiments.She first wishes to determine the calorimeter constant (C_cal)for her coffee cup calorimeter.She pours a 50.0 mL sample of water at 345 K into the calorimeter containing a 50.0 mL sample of water at 298 K.She carefully records the final temperature of the water as 317 K.What is the value of C_cal for the calorimeter?

A) 19 J/K
B) 28 J/K
C) 99 J/K
D) 21 J/K
E) 76 J/K

Question 25

Two solutions,initially at 24.60°C,are mixed in a coffee cup calorimeter.When a 100.0 mL volume of 0.100 M AgNO₃ solution is mixed with a 100.0 mL sample of 0.200 M NaCl solution,the temperature in the calorimeter rises to 25.30°C.Determine the DH°_rxn for the reaction as written below.Assume that the density and heat capacity of the solutions is the same as that of water.
NaCl(aq)+ AgNO₃(aq)→ AgCl(s)+ NaNO₃(aq)DH°_rxn = ?

A) -35 kJ
B) -59 kJ
C) -250 kJ
D) -16 kJ
E) -140 kJ

Question 26

A piece of iron (mass = 25.0 g)at 398 K is placed in a styrofoam coffee cup containing 25.0 mL of water at 298 K.Assuming that no heat is lost to the cup or the surroundings,what will the final temperature of the water be? The specific heat capacity of iron = 0.449 J/g°C and water = 4.18 J/g°C.

A) 348 K
B) 308 K
C) 287 K
D) 325 K
E) 388 K

Question 27

Using the following equation for the combustion of octane,calculate the heat associated with the formation of 100.0 g of carbon dioxide.The molar mass of octane is 114.33 g/mole.The molar mass of carbon dioxide is 44.0095 g/mole. 2 C₈H₁₈ + 25 O₂ → 16 CO₂ + 18 H₂O ΔH°_rxn = -11018 kJ

A) 12520 kJ
B) 1564 kJ
C) 1001 kJ
D) 1391 kJ
E) 11018 kJ

Question 28

Using the following equation for the combustion of octane,calculate the heat associated with the combustion of excess octane with 100.0 g of oxygen assuming complete combustion.The molar mass of octane is 114.33 g/mole.The molar mass of oxygen is 31.9988 g/mole. 2 C₈H₁₈ + 25 O₂ → 16 CO₂ + 18 H₂O ΔH°_rxn = -11018 kJ

A) -17220 kJ
B) -2152 kJ
C) -4304 kJ
D) -11018 kJ
E) -1337 kJ

Question 29

Using the following equation for the combustion of octane,calculate the heat associated with the combustion of 100.0 g of octane assuming complete combustion.The molar mass of octane is 114.33 g/mole.The molar mass of oxygen is 31.9988 g/mole. 2 C₈H₁₈ + 25 O₂ → 16 CO₂ + 18 H₂O ΔH°_rxn = -11018 kJ

A) -535.4 kJ
B) -4819 kJ
C) -602.3 kJ
D) -385.5 kJ
E) -11018 kJ

Question 30

A 35.6 g sample of ethanol (C₂H₅OH)is burned in a bomb calorimeter,according to the following reaction.If the temperature rose from 35.0 to 76.0°C and the heat capacity of the calorimeter is 23.3 kJ/°C,what is the value of DH°_rxn? The molar mass of ethanol is 46.07 g/mol.
C₂H₅OH(l)+ 3 O₂(g)→ 2 CO₂(g)+ 3 H₂O(g)ΔH°_rxn = ?

A) -1.24 × 10³ kJ/mol
B) +1.24 × 10³ kJ/mol
C) -8.09 × 10³ kJ/mol
D) -9.55 × 10³ kJ/mol
E) +9.55 × 10³ kJ/mol

Question 31

A 100.0 mL sample of 0.300 M NaOH is mixed with a 100.0 mL sample of 0.300 M HNO₃ in a coffee cup calorimeter.If both solutions were initially at 35.00°C and the temperature of the resulting solution was recorded as 37.00°C,determine the ΔH°_rxn (in units of kJ/mol NaOH)for the neutralization reaction between aqueous NaOH and HCl.Assume 1)that no heat is lost to the calorimeter or the surroundings,and 2)that the density and the heat capacity of the resulting solution are the same as water.

A) -55.7 kJ/mol NaOH
B) -169 kJ/mol NaOH
C) -16.7 kJ/mol NaOH
D) -27.9 kJ/mol NaOH
E) - 34.4 kJ/mol NaOH

Question 32

Given w = 0,an endothermic reaction has the following.

A) +ΔH and -ΔE
B) -ΔH and +ΔE
C) +ΔH and +ΔE
D) -ΔH and -ΔE

Question 33

What volume of benzene (C₆H₆,d= 0.88 g/mL,molar mass = 78.11 g/mol)is required to produce of heat according to the following reaction? 2 C₆H₆(l)+ 15 O₂(g)→ 12 CO₂(g)+ 6 H₂O(g)ΔH°_rxn = -6278 kJ

A) 75 mL
B) 37 mL
C) 21 mL
D) 19 mL
E) 42 mL

Question 34

Which of the following statements is TRUE?

A) State functions do not depend on the path taken to arrive at a particular state.
B) DE_rxn can be determined using constant volume calorimetry.
C) Energy is neither created nor destroyed, excluding nuclear reactions.
D) ΔH_rxn can be determined using constant pressure calorimetry.
E) All of the above are true.

Question 35

Two aqueous solutions are both at room temperature and are then mixed in a coffee cup calorimeter.The reaction causes the temperature of the resulting solution to fall below room temperature.Which of the following statements is TRUE?

A) The products have a lower potential energy than the reactants.
B) This type of experiment will provide data to calculate ΔE_rxn.
C) The reaction is exothermic.
D) Energy is leaving the system during reaction.
E) None of the above statements is true.

Question 36

According to the following thermochemical equation,what mass of HF (in g)must react in order to produce 345 kJ of energy? Assume excess SiO₂. SiO₂(s)+ 4 HF(g)→ SiF₄(g)+ 2 H₂O(l)ΔH°_rxn = -184 kJ

A) 42.7 g
B) 37.5 g
C) 150. g
D) 107 g
E) 173 g

Question 37

According to the following reaction,how much energy is evolved during the reaction of 32.5 g B₂H₆ and 72.5 g Cl₂? The molar mass of B₂H₆ is 27.67 g/mol. B₂H₆(g)+ 6 Cl₂(g)→ 2 BCl₃(g)+ 6 HCl(g)ΔH°_rxn = -1396 kJ

A) 1640 kJ
B) 238 kJ
C) 1430 kJ
D) 3070 kJ
E) 429 kJ

Question 38

Which statement is FALSE?

A) An exothermic reaction gives off heat to the surroundings.
B) Enthalpy is the sum of a system's internal energy and the product of pressure and volume.
C) ΔE_rxn is a measure of heat.
D) ΔH_rxn is the heat of reaction.
E) Endothermic has a positive ΔH.

Question 39

An exothermic reaction has

A) a negative ΔH, absorbs heat from the surroundings, and feels cold to the touch.
B) a positive ΔH, gives off heat to the surroundings, and feels warm to the touch.
C) a negative ΔH, gives off heat to the surroundings, and feels warm to the touch.
D) a positive ΔH, absorbs heat from the surroundings, and feels cold to the touch.
E) a positive ΔH, absorbs heat from the surroundings, and feels warm to the touch.

Question 40

Using the following thermochemical equation,determine the amount of heat produced per kg of CO₂ formed during the combustion of benzene (C₆H₆). 2 C₆H₆(l)+ 15 O₂(g)→ 12 CO₂(g)+ 6 H₂O(g)ΔH°_rxn = -6278 kJ

A) 1.43 × 10⁵ kJ/kg CO₂
B) 2.30 × 10⁴ kJ/kg CO₂
C) 4.34 × 10⁴ kJ/kg CO₂
D) 1.19 × 10⁴ kJ/kg CO₂
E) 8.40 × 10⁵ kJ/kg CO₂

Question 41

Use the ΔH°_f and ΔH°_rxn information provided to calculate ΔH°_f for IF: ΔH°_{f (kJ/mol)} IF₇(g)+ I₂(g)→ IF₅(g)+ 2 IF(g)ΔH°_rxn = -89 kJ
IF₇(g)-941
IF₅(g)-840

A) 101 kJ/mol
B) -146 kJ/mol
C) -190. kJ/mol
D) -95 kJ/mol
E) 24 kJ/mol

Question 42

Use the ΔH°_f and ΔH°_rxn information provided to calculate ΔH°_f for SO₃(g): ΔH°_{f (kJ/mol)} 2 SO₂(g)+ O₂(g)→ 2 SO₃(g)ΔH°_rxn = -198 kJ
SO₂(g)-297

A) -792 kJ/mol
B) -248 kJ/mol
C) -495 kJ/mol
D) -578 kJ/mol
E) -396 kJ/mol

Question 43

Use the information provided to determine ΔH°_rxn for the following reaction: ΔH°_f (kJ/mol)CH₄(g)+ 3 Cl₂(g)→ CHCl₃(l)+ 3 HCl(g)ΔH°_rxn = ?
CH₄(g)-75
CHCl₃(l)-134
HCl(g)-92

A) -151 kJ
B) -335 kJ
C) +662 kJ
D) +117 kJ
E) -217 kJ

Question 44

Use the information provided to determine ΔH°_rxn for the following reaction: ΔH°_f (kJ/mol)CH₄(g)+ 4 Cl₂(g)→ CCl₄(g)+ 4 HCl(g)ΔH°_rxn = ?
CH₄(g)-75
CCl₄(g)-96
HCl(g)-92

A) -389 kJ
B) -113 kJ
C) +113 kJ
D) -71 kJ
E) +79 kJ

Question 45

Which of the following is NOT a major contributor to energy consumption?

A) residential
B) commercial
C) transportation
D) industrial
E) atmospheric

Question 46

Identify the compound that is NOT a major air pollutant.

A) water
B) sulfur oxides
C) nitrogen oxides
D) carbon monoxide
E) ozone

Question 47

Use the standard reaction enthalpies given below to determine ΔH°_rxn for the following reaction: 2 NO(g)+ O₂(g)→ 2 NO₂(g)ΔH°_rxn = ?
Given:
N₂(g)+ O₂(g)→ 2 NO(g)ΔH°_rxn = +183 kJ
1/2 N₂(g)+ O₂(g)→ NO₂(g)ΔH°_rxn = +33 kJ

A) -150. kJ
B) -117 kJ
C) -333 kJ
D) +115 kJ
E) +238 kJ

Question 48

Use the information provided to determine ΔH°_rxn for the following reaction: ΔH°_f (kJ/mol)3 Fe₂O₃(s)+ CO(g)→ 2 Fe₃O₄(s)+ CO₂(g)ΔH°_rxn = ?
Fe₂O₃(s)-824
Fe₃O₄(s)-1118
CO(g)-111
CO₂(g)-394

A) +277 kJ
B) -577 kJ
C) -47 kJ
D) +144 kJ
E) -111 kJ

Question 49

For a process at constant pressure,5350 joules are released.This quantity is equivalent to

A) 2.320 × 10³ cal.
B) 2.238 × 10⁴ cal.
C) 1.279 × 10³ cal.
D) 1.277 × 10⁴ cal.
E) 3.200 cal.

Question 50

Which of the following statements is TRUE?

A) The burning of fossil fuels contributes to global warming.
B) Cars that run on hydrogen fuel cells are environmentally friendly.
C) The more energy produced per kg of CO₂ produced, the better the fuel.
D) Acid rain is one of the problems associated with the combustion of fossil fuels.
E) All of the above are true.

Question 51

Which of the following is TRUE if ΔE_sys = -100 J?

A) The system is gaining 100 J, while the surroundings are losing 100 J.
B) The system is losing 100 J, while the surroundings are gaining 100 J.
C) Both the system and the surroundings are gaining 100 J.
D) Both the system and the surroundings are losing 100 J.
E) None of the above is true.

Question 52

Use the standard reaction enthalpies given below to determine ΔH°_rxn for the following reaction: 4 SO₃(g)→ 4 S(s)+ 6 O₂(g)ΔH°_rxn = ?
Given:
SO₂(g)→ S(s)+ O₂(g)ΔH°_rxn = +296.8 kJ
2 SO₂(g)+ O₂(g)→ 2 SO₃(g)ΔH°_rxn = -197.8 kJ

A) -494.6 kJ
B) -692.4 kJ
C) -791.4 kJ
D) 1583 kJ
E) -293.0 kJ

Question 53

Use the ?H°_f information provided to calculate ?H°_rxn for the following: ?H°_f (kJ/mol) SO₂Cl₂(g)+ 2 H₂O(l)? 2 HCl(g)+ H₂SO4(l)

?H°_rxn = ?

SO₂Cl₂(g)-364
H₂O(l)-286
HCl(g)-92
H₂SO₄(l)-814

A) -256 kJ
B) +161 kJ
C) -62 kJ
D) +800. kJ
E) -422 kJ

Question 54

For a process at constant pressure,12,400 calories of heat are released.This quantity of heat is equivalent to

A) 1.92 × 10^-5 J.
B) 5.92 × 10³ J.
C) 6.21 × 10⁴ J.
D) 5.19 × 10⁴ J.
E) 8.85 × 10⁵ J.

Question 55

Which of the following is the major contributor to energy consumption?

A) residential
B) commercial
C) transportation
D) industrial
E) atmospheric

Question 56

Use the standard reaction enthalpies given below to determine ΔH°_rxn for the following reaction: P₄(g)+ 10 Cl₂(g)→ 4 PCl₅(s)ΔH°_rxn = ?
Given:
PCl₅(s)→ PCl₃(g)+ Cl₂(g)ΔH°_rxn = +157 kJ
P₄(g)+ 6 Cl₂(g)→ 4 PCl₃(g)ΔH°_rxn = -1207 kJ

A) -1835 kJ
B) -1364 kJ
C) -1050. kJ
D) -1786 kJ
E) -2100. kJ

Question 57

Identify the energy source with the highest negative ΔH°_rxn.

A) 1 mole ethanol
B) 1 mole methane
C) 1 mole carbon
D) 1 mole petroleum
E) All have the same value.

Question 58

Choose the thermochemical equation that illustrates ΔH°_f for Li₂SO₄.

A) 2 Li⁺(aq) + SO₄^2-(aq) → Li₂SO₄(aq)
B) 2 Li(s) + 1/8 S₈(s, rhombic) + 2 O₂(g) → Li₂SO₄(s)
C) Li₂SO₄(aq) → 2 Li⁺(aq) + SO₄^2-(aq)
D) 8 Li₂SO₄(s) → 16 Li(s) + S₈(s, rhombic) + 16 O₂(g)
E) 16 Li(s) + S₈(s, rhombic) + 16 O₂(g) → 8 Li₂SO₄(s)

Question 59

Use the standard reaction enthalpies given below to determine ΔH°_rxn for the following reaction: 2 S(s)+ 3 O₂(g)→ 2 SO₃(g)ΔH°_rxn = ?
Given:
SO₂(g)→ S(s)+ O₂(g)ΔH°_rxn = +296.8 kJ
2 SO₂(g)+ O₂(g)→ 2 SO₃(g)ΔH°_rxn = -197.8 kJ

A) -494.6 kJ
B) -692.4 kJ
C) -791.4 kJ
D) 1583 kJ
E) -293.0 kJ

Question 60

Two solutions,initially at 24.69°C,are mixed in a coffee cup calorimeter.When a 200.0 mL volume of 0.100 M AgNO₃ solution is mixed with a 100.0 mL sample of 0.100 M NaCl solution,the temperature in the calorimeter rises to 25.16°C.Determine the DH°_rxn,in units of kJ/mol AgCl.Assume that the density and heat capacity of the solutions is the same as that of water.Hint: Write a balanced reaction for the process.

A) -32 kJ/mol AgCl
B) -78 kJ/mol AgCl
C) -59 kJ/mol AgCl
D) -25 kJ/mol AgCl
E) -62 kJ/mol AgCl

Question 61

Define heat capacity.

A) the quantity of heat required to raise the temperature of 1 mole of a substance by 1°F
B) the quantity of heat required to change a system's temperature by 1°C
C) the quantity of heat required to raise the temperature of 1 gram of a substance by 1°C
D) the quantity of heat required to raise the temperature of 1 gram of a substance by 1°F
E) the quantity of heat required to raise the temperature of 1 liter of a substance by 1°F

Question 62

Which of the following is TRUE if ΔE_sys = 260 J?

A) The system is gaining 260 J, while the surroundings are losing 260 J.
B) The system is losing 260 J, while the surroundings are gaining 260 J.
C) Both the system and the surroundings are gaining 260 J.
D) Both the system and the surroundings are losing 260 J.
E) None of the above is true.

Question 63

Calculate the amount of heat (in kJ)necessary to raise the temperature of 51.8 g benzene by 52.6 K.The specific heat capacity of benzene is 1.05 J/g°C.

A) 1.81 kJ
B) 16.6 kJ
C) 2.59 kJ
D) 2.86 kJ
E) 3.85 kJ

Question 64

The specific heat capacity of liquid mercury is 0.14 J/gK.How many joules of heat are needed to raise the temperature of 7.25 g of mercury from 36.0°C to 75.0°C?

A) 2.0 × 10³ J
B) 40 J
C) 113 J
D) 5.0 × 10^-4 J
E) 2.1 J

Question 65

Define specific heat capacity.

A) the quantity of heat required to raise the temperature of 1 mole of a substance by 1°C
B) the quantity of heat required to change a system's temperature by 1°C
C) the quantity of heat required to raise the temperature of 1 gram of a substance by 1°C
D) the quantity of heat required to raise the temperature of 1 kilogram of a substance by 1°F
E) the quantity of heat required to raise the temperature of 1 liter of a substance by 1°F

Question 66

Give the units of heat capacity.

A) J/°C
B) Jg/ °F
C) J/mole°C
D) g/°F
E) mole/°F

Question 67

Calculate the kinetic energy of a 150 g baseball moving at a speed of 37.m/s (83 mph).

A) 5.4 J
B) 1.0 × 10² J
C) 5.7 × 10³ J
D) 1.0 × 10⁵ J
E) 2.1 × 10² J

Question 68

Define molar heat capacity.

A) the quantity of heat required to raise the temperature of 1 mole of a substance by 1°C
B) the quantity of heat required to change a system's temperature by 1°F
C) the quantity of heat required to raise the temperature of 1 gram of a substance by 1°C
D) the quantity of heat required to raise the temperature of 1 gram of a substance by 1°F
E) the quantity of heat required to lower the temperature of 1 liter of a substance by 1°C

Question 69

A piece of iron (C = 0.449 J/g°C)and a piece of gold (C = 0.128 J/g°C)have identical masses.If the iron has an initial temperature of 468 K and the gold has an initial temperature of 328 K,which of the following statements is TRUE of the outcome when the two metals are placed in contact with one another? Assume no heat is lost to the surroundings.

A) Since the two metals have the same mass, the final temperature of the two metals will be 398 K, exactly halfway between the two initial temperatures.
B) Since the two metals have the same mass, but the specific heat capacity of gold is much smaller than that of iron, the final temperature of the two metals will be closer to 328 K than to 468 K.
C) Since the two metals have the same mass, the thermal energy contained in the iron and gold after reaching thermal equilibrium will be the same.
D) Since the two metals have the same mass, the thermal energy contained in each metal after equilibrium will be the same.
E) None of the above is true.

Question 70

Calculate the work,w,gained or lost by the system when a gas expands from 15 L to 50 L against a constant external pressure of 1.5 atm.101.3 L ∙ atm = 101 J

A) -7.6 kJ
B) -5.3 kJ
C) +5.3 kJ
D) +7.6 kJ

Question 71

Give the units of molar heat capacity.

A) J/°F
B) J/g °C
C) J/mole°C
D) g/°C
E) gmole °F

Question 72

The specific heat capacity of solid copper metal is 0.385 J/gK.How many joules of heat are needed to raise the temperature of a 1.15-kg block of copper from 25.0°C to 66.0°C?

A) 1.22 × 10⁵ J
B) 18.2 J
C) 1.82 × 10⁴ J
D) 8.17 × 10^-6 J
E) 0.00817 J

Question 73

Which of the following (with specific heat capacity provided)would show the smallest temperature change upon gaining 200.0 J of heat?

A) 50.0 g water, C_water = 4.18|1.23 J/g°C
B) 50.0 g Fe, C_Fe = 0.449 J/g°C
C) 25.0 g granite, C_granite = 0.79 J/g°C
D) 25.0 g Pb, C_Pb = 0.128 J/g°C
E) 25.0 g Ag, C_Ag= 0.235 J/g°C

Question 74

Which of the following (with specific heat capacity provided)would show the largest temperature change upon gaining 200.0 J of heat?

A) 50.0 g ethanol, C_ethanol = 2.42 J/g°C
B) 50.0 g Zn, C_Zn = 0.39 J/g°C
C) 25.0 g sand, C_sand = 0.84 J/g°C
D) 25.0 g Au, C_Au = 0.128 J/g°C
E) 25.0 g Ag, C_Ag= 0.235 J/g°C

Question 75

Calculate the amount of heat (in kJ)required to raise the temperature of a 88.0 g sample of ethanol from 298.0 K to 405.0 K.The specific heat capacity of ethanol is 2.42 J/g°C.

A) 57.0 kJ
B) 22.8 kJ
C) 73.6 kJ
D) 30.4 kJ
E) 11.9 kJ

Question 76

Calculate the change internal energy (ΔE)for a system that is giving off 65.0 kJ of heat and is performing 855 J of work on the surroundings.

A) 64.1 kJ
B) -64.1 kJ
C) -65.9 kJ
D) 6.00 × 10² kJ
E) -6.00 × 10² kJ

Question 77

Which of the following substances (with specific heat capacity provided)would show the greatest temperature change upon absorbing 100.0 J of heat?

A) 10.0 g Ag, C_Ag = 0.235 J/g°C
B) 10.0 g Pb, = 0.160 J/g°C
C) 10.0 g water, C_water = 4.18 J/g°C
D) 10.0 g Fe, C_Fe = 0.449 J/g°C
E) 10.0 g Ca, C_Ca= 0.650 J/g°C

Question 78

A 6.50-g sample of liquid water at 25.0 C is heated by the addition of 145 J of energy.The final temperature of the water is ________°C.The specific heat capacity of liquid water is

A) 118
B) 25.2
C) -19.7
D) 30.3
E) 5.34

Question 79

Give the units of specific heat capacity.

A) Jg/°F
B)( ^J/g °C)
C) J/mole °C
D) g/°C
E) gmole °F

Question 80

A balloon is inflated from 0.0100 L to 0.600 L against an external pressure of 10.00 atm.How much work is done in joules? 101.3 J = 1 L × atm

A) -59.8 J
B) 59.8 J
C) 0.598 J
D) -0.598 J
E) -598 J