Question 1

Which of the following is not a type of energy or energy transfer?

Accepted Answer

A) chemical energy 
B) heat 
C) temperature 
D) work 
A) chemical energy 
B) heat 
C) temperature 
D) work

Question 2

Use the given standard enthalpies of formation to calculate ΔH° for the following reaction
3 Fe2O3(s)+ CO(g)→ 2 Fe3O4(s)+ CO2(g).

Accepted Answer

A) -5213.4 kJ 
B) -577.2 kJ 
C) -47.2 kJ 
D) +47.2 kJ 
A) -5213.4 kJ 
B) -577.2 kJ 
C) -47.2 kJ 
D) +47.2 kJ

Question 3

For the reaction,C H4(g)→ C(g)+ 4 H(g),one would expect

Accepted Answer

A) ΔH° to be negative and ΔS° to be negative. 
B) ΔH° to be negative and ΔS° to be positive. 
C) ΔH° to be positive and ΔS° to be negative. 
D) ΔH° to be positive and ΔS° to be positive. 
A) ΔH° to be negative and ΔS° to be negative. 
B) ΔH° to be negative and ΔS° to be positive. 
C) ΔH° to be positive and ΔS° to be negative. 
D) ΔH° to be positive and ΔS° to be positive.

Question 4

A reaction is performed in a water bath initially at 21°C which decreases to 18°C by the end of the reaction.For this reaction the sign of heat transfer is ________,and the reaction is classified as ________.

Accepted Answer

positive,e

Question 5

How much heat is absorbed when 45.00 g of C(s)reacts in the presence of excess SO2(g)to produce CS2(l)and CO(g)according to the following chemical equation?
5 C(s)+ 2 SO2(g)→ CS2(l)+ 4 CO(g)ΔH° = 239.9 kJ

Accepted Answer

A) 179.8 kJ 
B) 239.9 kJ 
C) 898.5 kJ 
D) 2158 kJ 
A) 179.8 kJ 
B) 239.9 kJ 
C) 898.5 kJ 
D) 2158 kJ

Question 6

Step (2)in the reaction is represented by

Accepted Answer

A) arrow A. 
B) arrow B. 
C) arrow C. 
D) line E. 
A) arrow A. 
B) arrow B. 
C) arrow C. 
D) line E.

Question 7

Heat transferred in a chemical reaction or physical change is expressed as ΔE when the heat is transferred under constant ________ and is expressed as ΔH when heat is transferred under constant ________ conditions.

Accepted Answer

The answer of Heat transferred in a chemical reaction or...

Question 8

What are the signs of ΔH,ΔS,and ΔG for the following spontaneous change?

Accepted Answer

A) ΔH = +,ΔS = +,ΔG = - 
B) ΔH = +,ΔS = -,ΔG = - 
C) ΔH = -,ΔS = +,ΔG = - 
D) ΔH = -,ΔS = -,ΔG = - 
A) ΔH = +,ΔS = +,ΔG = - 
B) ΔH = +,ΔS = -,ΔG = - 
C) ΔH = -,ΔS = +,ΔG = - 
D) ΔH = -,ΔS = -,ΔG = -

Question 9

Find ΔH for BaCO3 (s)→ BaO (s)+ CO2 (g)
Given 2 Ba (s)+ O2 (g)→ 2 BaO (s)ΔH = -1107.0 kJ
Ba (s)+ CO2 (g)+ 1/2 O2 (g)→ BaCO3 (g)ΔH = -822.5 kJ

Accepted Answer

A) -1929.5 kJ 
B) -1376.0 kJ 
C) -284.5 kJ 
D) 269.0 kJ 
A) -1929.5 kJ 
B) -1376.0 kJ 
C) -284.5 kJ 
D) 269.0 kJ

Question 10

Which is expected to have the most negative standard enthalpy of formation?

Accepted Answer

A) H2(g) 
B) O2(g) 
C) H2O(g) 
D) H2O(l) 
A) H2(g) 
B) O2(g) 
C) H2O(g) 
D) H2O(l)

Question 11

A property whose value depends only on the present condition of the system and not how the system arrived at that condition is called a ________ function.

Accepted Answer

The answer of A property whose value depends only on...

Question 12

For the reaction,NH3(g)→ N(g)+ 3 H(g),one would expect

Accepted Answer

A) ΔH° to be negative and ΔS° to be negative. 
B) ΔH° to be negative and ΔS° to be positive. 
C) ΔH° to be positive and ΔS° to be negative. 
D) ΔH° to be positive and ΔS° to be positive. 
A) ΔH° to be negative and ΔS° to be negative. 
B) ΔH° to be negative and ΔS° to be positive. 
C) ΔH° to be positive and ΔS° to be negative. 
D) ΔH° to be positive and ΔS° to be positive.

Question 13

The specific heat of copper is 0.385 J/(g ∙ °C).If 34.2 g of copper,initially at 24.0°C,absorbs
4)689 kJ,what will be the final temperature of the copper?

Accepted Answer

A) 24.4°C 
B) 26.8°C 
C) 356°C 
D) 380°C 
A) 24.4°C 
B) 26.8°C 
C) 356°C 
D) 380°C

Question 14

Sodium metal reacts with water to produce hydrogen gas and sodium hydroxide according to the chemical equation shown below.When 0.0 25 mol of Na is added to 100.00 g of water,the temperature of the resulting solution rises from 25.00°C to 35.75°C.If the specific heat of the solution is 4.18 J/(g ∙ °C),calculate ΔH for the reaction,as written.
2 Na(s)+ 2 H2O(l)→ 2 NaOH(aq)+ H2(g)ΔH= ?

Accepted Answer

A) -5.41 kJ 
B) -90.0 kJ 
C) -180 kJ 
D) -360 kJ 
A) -5.41 kJ 
B) -90.0 kJ 
C) -180 kJ 
D) -360 kJ

Question 15

At 253 K the sign of ΔG for the physical change shown below is ________.
H2O(s)→ H2O(l)

Accepted Answer

Question 16

For the reaction: A + 2 B → 3 C,ΔH° = -203 kJ.For the reaction 6 C → 2 A + 4 B,ΔH° = ________ kJ.

Accepted Answer

The answer of For the reaction: A + 2 B...

Question 17

Sodium metal reacts with water to produce hydrogen gas and sodium hydroxide according to the chemical equation shown below.When 0.0300 mol of Na is added to 100.00 g of water,the temperature of the resulting solution rises from 25.00°C to 37.90°C.If the specific heat of the solution is
4)18 J/(g ∙ °C),calculate ΔH for the reaction,as written.
2 Na(s)+ 2 H2O(l)→ 2 NaOH(aq)+ H2(g)ΔH = ?

Accepted Answer

A) -5.41 kJ 
B) -90.0 kJ 
C) -180 kJ 
D) -362 kJ 
A) -5.41 kJ 
B) -90.0 kJ 
C) -180 kJ 
D) -362 kJ

Question 18

Which is expected to have the lowest specific heat capacity at 25°C?

Accepted Answer

A) air 
B) copper 
C) polyethylene 
D) water 
A) air 
B) copper 
C) polyethylene 
D) water

Question 19

The enthalpy of fusion,or heat of fusion (ΔHfusion),of water is positive and corresponds to which physical change?

Accepted Answer

A) H2O(g)→ H2O(s) 
B) H2O(l)→ H2O(s) 
C) H2O(s)→ H2O(l) 
D) H2O(s)→ H2O(g) 
A) H2O(g)→ H2O(s) 
B) H2O(l)→ H2O(s) 
C) H2O(s)→ H2O(l) 
D) H2O(s)→ H2O(g)

Question 20

For a process at constant volume,

Accepted Answer

A) q = 0,w = 0,and ΔE = 0. 
B) w = 0 and ΔE = q. 
C) w = 0 and ΔH = q. 
D) w = 0 and ΔE = ΔH. 
A) q = 0,w = 0,and ΔE = 0. 
B) w = 0 and ΔE = q. 
C) w = 0 and ΔH = q. 
D) w = 0 and ΔE = ΔH.

Exam 8: Thermochemistry: Chemical Energy

Which of the following is not a type of energy or energy transfer?

Use the given standard enthalpies of formation to calculate ΔH° for the following reaction 3 Fe2O3(s)+ CO(g)→ 2 Fe3O4(s)+ CO2(g).

For the reaction,C H4(g)→ C(g)+ 4 H(g),one would expect

A reaction is performed in a water bath initially at 21°C which decreases to 18°C by the end of the reaction.For this reaction the sign of heat transfer is ________,and the reaction is classified as ________.

How much heat is absorbed when 45.00 g of C(s)reacts in the presence of excess SO2(g)to produce CS2(l)and CO(g)according to the following chemical equation? 5 C(s)+ 2 SO2(g)→ CS2(l)+ 4 CO(g)ΔH° = 239.9 kJ

Step (2)in the reaction is represented by

Heat transferred in a chemical reaction or physical change is expressed as ΔE when the heat is transferred under constant ________ and is expressed as ΔH when heat is transferred under constant ________ conditions.

What are the signs of ΔH,ΔS,and ΔG for the following spontaneous change?

Find ΔH for BaCO3 (s)→ BaO (s)+ CO2 (g) Given 2 Ba (s)+ O2 (g)→ 2 BaO (s)ΔH = -1107.0 kJ Ba (s)+ CO2 (g)+ 1/2 O2 (g)→ BaCO3 (g)ΔH = -822.5 kJ

Which is expected to have the most negative standard enthalpy of formation?

A property whose value depends only on the present condition of the system and not how the system arrived at that condition is called a ________ function.

For the reaction,NH3(g)→ N(g)+ 3 H(g),one would expect

The specific heat of copper is 0.385 J/(g ∙ °C).If 34.2 g of copper,initially at 24.0°C,absorbs 4)689 kJ,what will be the final temperature of the copper?

At 253 K the sign of ΔG for the physical change shown below is ________. H2O(s)→ H2O(l)

For the reaction: A + 2 B → 3 C,ΔH° = -203 kJ.For the reaction 6 C → 2 A + 4 B,ΔH° = ________ kJ.

Which is expected to have the lowest specific heat capacity at 25°C?

The enthalpy of fusion,or heat of fusion (ΔHfusion),of water is positive and corresponds to which physical change?

For a process at constant volume,

Chemistry: Matter and Measurement

Atoms, molecules, and Ions

Formulas, equations, and Moles

Reactions in Aqueous Solutions

Periodicity and the Atomic Structure of Atoms

Ionic Bonds and Some Main-Group Chemistry

Covalent Bonds and Molecular Structure

Gases: Their Properties and Behavior

Liquids,solids,and Phase Changes

Solutions and Their Properties

Chemical Kinetics

Chemical Equilibrium

Aqueous Equilibria: Acids and Bases

Applications of Aqueous Equilibria

Thermodynamics: Entropy, free Energy, and Equilibrium

Electrochemistry

Hydrogen, oxygen, and Water

The Main-Group Elements

Transition Elements and Coordination Chemistry

Metals and Solid-State Materials

Nuclear Chemistry

Organic and Biological Chemistry

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Use the given standard enthalpies of formation to calculate ΔH° for the following reaction 3 Fe₂O₃(s)+ CO(g)→ 2 Fe₃O₄(s)+ CO₂(g).

For the reaction,CH₄(g)→ C(g)+ 4 H(g),one would expect

A reaction is performed in a water bath initially at 21°C which decreases to 18°C by the end of the reaction.For this reaction the sign of heat transfer is ,and the reaction is classified as .

How much heat is absorbed when 45.00 g of C(s)reacts in the presence of excess SO₂(g)to produce CS₂(l)and CO(g)according to the following chemical equation? 5 C(s)+ 2 SO₂(g)→ CS₂(l)+ 4 CO(g)ΔH° = 239.9 kJ

Heat transferred in a chemical reaction or physical change is expressed as ΔE when the heat is transferred under constant and is expressed as ΔH when heat is transferred under constant conditions.

Find ΔH for BaCO₃ (s)→ BaO (s)+ CO₂ (g) Given 2 Ba (s)+ O₂ (g)→ 2 BaO (s)ΔH = -1107.0 kJ Ba (s)+ CO₂ (g)+ 1/2 O₂ (g)→ BaCO₃ (g)ΔH = -822.5 kJ

For the reaction,NH₃(g)→ N(g)+ 3 H(g),one would expect

At 253 K the sign of ΔG for the physical change shown below is ________. H₂O(s)→ H₂O(l)

The enthalpy of fusion,or heat of fusion (ΔH_fusion),of water is positive and corresponds to which physical change?