Combine the reactions: P4(s)+ 6 Cl2(g)→ 4 PCl3(g)ΔrH°298 = -1225.0 kJ/mol PCl3(g)+ 3 H2O(l)→ H3PO3(aq)+ 3 HCl(g)= -853.5 kJ/mol 2 H2(g)+ O2(g)→ 2 H2O(l)= -571.5 kJ/mol H2(g)+ Cl2(g)→ 2 HCl(g)= -184.9 kJ/mol To obtain the reaction: P4(s)+ 6 H2(g)+ 6 O2(g)→ 4 H3PO3(aq). What is the value of ΔrH°298 for this reaction?

A) -2465.1 kJ/mol B) -6958.6 kJ/mol C) -2834.9 kJ/mol D) -9177.4 kJ/mol E) 8605.9 kJ/mol A) -2465.1 kJ/mol B) -6958.6 kJ/mol C) -2834.9 kJ/mol D) -9177.4 kJ/mol E) 8605.9 kJ/mol B

How much heat is absorbed/released when 40.00 g of NH3(g)reacts in the presence of excess O2(g) to produce NO(g)and H2O(l)according to the following chemical equation? 4 NH3(g)+ 5 O2(g)→ 4 NO(g)+ 6 H2O(l) H° = 1168 kJ

A) 685.8 kJ of heat are absorbed. B) 685.8 kJ of heat are released. C) 2743 kJ of heat are absorbed. D) 2743 kJ of heat are released. A) 685.8 kJ of heat are absorbed. B) 685.8 kJ of heat are released. C) 2743 kJ of heat are absorbed. D) 2743 kJ of heat are released.

What is the work done in joules by the system when H2 expands against a constant pressure of 75 atm at 45.3 °C? The change in volume is 24.0 L.

A) 1.8 × 103 J B) -8.2 × 104 J C) 8.2 × 104 J D) 1.8 × 105 J E) -1.8 × 105 J A) 1.8 × 103 J B) -8.2 × 104 J C) 8.2 × 104 J D) 1.8 × 105 J E) -1.8 × 105 J

Exam 7: Thermochemistry

Combine the reactions: P₄(s)+ 6 Cl₂(g)→ 4 PCl₃(g)Δ_rH°₂₉₈ = -1225.0 kJ/mol PCl₃(g)+ 3 H₂O(l)→ H₃PO₃(aq)+ 3 HCl(g)= -853.5 kJ/mol 2 H₂(g)+ O₂(g)→ 2 H₂O(l)= -571.5 kJ/mol H₂(g)+ Cl₂(g)→ 2 HCl(g)= -184.9 kJ/mol To obtain the reaction: P₄(s)+ 6 H₂(g)+ 6 O₂(g)→ 4 H₃PO₃(aq). What is the value of Δ_rH°₂₉₈ for this reaction?

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Question 1

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A 12-inch diameter ball of pure cobalt metal at 225 °C was placed in 10.0 gal.of water at 15.0 °C.What is the final temperature of the water? Assume no heat is lost to the surroundings.(specific heat for cobalt is 0.421 J/g °C,density of cobalt = 8.862 g/cm³,1 gal.= 3.785 L,1 in = 2.54 cm,V(sphere)= 4/3 πr³)

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Question 2

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Calculate the enthalpy change for the following reaction at 25 °C.The value of Δ_fH° in kJ/mol is given below each species:

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Question 3

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The standard heat of formation of solid ammonium bromide is -270.8 kJ/mol.Write the chemical equation for the reaction to which this value applies.

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Question 4

A 50.0 g sample of liquid water at 25.0 °C is mixed with 23.0 g of water at 89.0 °C.The final temperature of the water is ________ °C.

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Question 5

Enthalpy is defined as:

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Question 6

An expansion of gas by a system means that the system does work.

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Question 7

The complete combustion of 1 mole of nitrobenzene,C₆H₅NO₂,in a bomb calorimeter liberates 3088 kJ of heat and increases the temperature of the calorimeter assembly by 140.0 °C.What is the heat capacity of this bomb calorimeter?

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Question 8

The final temperature when 150 mL of water at 90.0 °C is added to 100.0 mL of water at 30.0 °C is around ________.

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Question 9

Lead,water,sulfur and arsenic have specific heats of 0.128,4.18,0.706,and 0.329 J g^-1 °C^-1,respectively.Which of the following would need the smallest quantity of heat to change the temperature of 5 g by 10 °C?

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Question 10

Calculate the standard enthalpy of formation of Cl^-(aq),given the following thermochemical data at 1 atm,and knowing that the standard enthalpies of formation of H₂(g)and H⁺(aq)are both zero. HCl(g)→ H⁺(aq)+ Cl^-(aq)Δ_rH° = -75.15 kJ/mol H₂(g)+ Cl₂(g)→ 2HCl(g)Δ_rH° = -184.62 kJ/mol

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Question 11

Heat is usually transferred from a cold object to a hot object.

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Question 12

When 2.50 g of Ba(s)is added to 100.00 g of water in a container open to the atmosphere,the reaction shown below occurs and the temperature of the resulting solution rises from 22.00 °C to 40.32 °C.If the specific heat of the solution is 4.18 J g^-1°C^-1 ,calculate For the reaction,as written. Ba(s)+ 2 H₂O(l)→ Ba(OH)₂(aq)+ H₂(g) = ?

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Question 13

How much heat is absorbed/released when 40.00 g of NH₃(g)reacts in the presence of excess O₂(g) to produce NO(g)and H₂O(l)according to the following chemical equation? 4 NH₃(g)+ 5 O₂(g)→ 4 NO(g)+ 6 H₂O(l) H° = 1168 kJ

(Multiple Choice)

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Question 14

What is the final temperature in the bomb calorimeter if 1.785 grams of benzoic acid (C₆H₅COOH)is combusted in a calorimeter with a heat capacity of 5.02 kJ/ °C and initial temperature of 24.62 °C? The heat of combustion of benzoic acid is -26.42 kJ/g.

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Question 15

The combustion of titanium with oxygen produces titanium dioxide: Ti(s)+ O₂(g)→TiO₂ (s) When 2.060 g of titanium is combusted in a bomb calorimeter,the temperature of the calorimeter increases from 25.00 °C to 91.60 °C.In a separate experiment,the heat capacity of the calorimeter is measured to be 9.84 kJK^-1 .The heat of reaction for the combustion of a mole of Ti in this calorimeter is ________ kJ mol^-1.

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Question 16

What is the work done in joules by the system when H₂ expands against a constant pressure of 75 atm at 45.3 °C? The change in volume is 24.0 L.

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Question 17

What is the reaction for the standard enthalpy of formation for HCl(g)?

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Question 18

Calculate the amount of heat absorbed by a 40.0 g sample of water at 21 °C when the temperature is raised to 35 °C.

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Question 19

When power was turned off to a 30.0 gal.water heater,the temperature of the water dropped from 75.0 °C to 22.5 °C.How much heat was lost to the surroundings?

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Question 20

Showing 1 - 20 of 125

Exam 7: Thermochemistry

Calculate the enthalpy change for the following reaction at 25 °C.The value of ΔfH° in kJ/mol is given below each species:

The standard heat of formation of solid ammonium bromide is -270.8 kJ/mol.Write the chemical equation for the reaction to which this value applies.

A 50.0 g sample of liquid water at 25.0 °C is mixed with 23.0 g of water at 89.0 °C.The final temperature of the water is ________ °C.

Enthalpy is defined as:

An expansion of gas by a system means that the system does work.

The complete combustion of 1 mole of nitrobenzene,C6H5NO2,in a bomb calorimeter liberates 3088 kJ of heat and increases the temperature of the calorimeter assembly by 140.0 °C.What is the heat capacity of this bomb calorimeter?

The final temperature when 150 mL of water at 90.0 °C is added to 100.0 mL of water at 30.0 °C is around ________.

Lead,water,sulfur and arsenic have specific heats of 0.128,4.18,0.706,and 0.329 J g-1 °C-1,respectively.Which of the following would need the smallest quantity of heat to change the temperature of 5 g by 10 °C?

Calculate the standard enthalpy of formation of Cl-(aq),given the following thermochemical data at 1 atm,and knowing that the standard enthalpies of formation of H2(g)and H+(aq)are both zero. HCl(g)→ H+(aq)+ Cl-(aq)ΔrH° = -75.15 kJ/mol H2(g)+ Cl2(g)→ 2HCl(g)ΔrH° = -184.62 kJ/mol

Heat is usually transferred from a cold object to a hot object.

How much heat is absorbed/released when 40.00 g of NH3(g)reacts in the presence of excess O2(g) to produce NO(g)and H2O(l)according to the following chemical equation? 4 NH3(g)+ 5 O2(g)→ 4 NO(g)+ 6 H2O(l) H° = 1168 kJ

What is the final temperature in the bomb calorimeter if 1.785 grams of benzoic acid (C6H5COOH)is combusted in a calorimeter with a heat capacity of 5.02 kJ/ °C and initial temperature of 24.62 °C? The heat of combustion of benzoic acid is -26.42 kJ/g.

What is the work done in joules by the system when H2 expands against a constant pressure of 75 atm at 45.3 °C? The change in volume is 24.0 L.

What is the reaction for the standard enthalpy of formation for HCl(g)?

Calculate the amount of heat absorbed by a 40.0 g sample of water at 21 °C when the temperature is raised to 35 °C.

When power was turned off to a 30.0 gal.water heater,the temperature of the water dropped from 75.0 °C to 22.5 °C.How much heat was lost to the surroundings?

Matter: Its Properties and Measurement

Atoms and the Atomic Theory

Chemical Compounds

Chemical Reactions

Introduction to Reactions in Aqueous Solutions

Gases

Electrons in Atoms

The Periodic Table and Some Atomic Properties

Chemical Bonding I: Basic Concepts

Chemical Bonding Ii: Valence Bond and Molecular Orbital Theories

Intermolecular Forces: Liquids and Solids

Spontaneous Change: Entropy and Gibbs Energy

Solutions and Their Physical Properties

Principles of Chemical Equilibrium

Acids and Bases

Additional Aspects of Acidbase Equilibria

Solubility and Complex-Ion Equilibria

Electrochemistry

Chemical Kinetics

Chemistry of the Main-Group Elements I: Groups 1,2,13,and 14

Chemistry of the Main-Group Elements Ii: Groups 18,17,16,15,and Hydrogen

The Transition Elements

Complex Ions and Coordination Compounds

Nuclear Chemistry

Structures of Organic Compounds

Reactions of Organic Compounds

Chemistry of the Living State

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Calculate the enthalpy change for the following reaction at 25 °C.The value of Δ_fH° in kJ/mol is given below each species:

The complete combustion of 1 mole of nitrobenzene,C₆H₅NO₂,in a bomb calorimeter liberates 3088 kJ of heat and increases the temperature of the calorimeter assembly by 140.0 °C.What is the heat capacity of this bomb calorimeter?

Lead,water,sulfur and arsenic have specific heats of 0.128,4.18,0.706,and 0.329 J g^-1 °C^-1,respectively.Which of the following would need the smallest quantity of heat to change the temperature of 5 g by 10 °C?

How much heat is absorbed/released when 40.00 g of NH₃(g)reacts in the presence of excess O₂(g) to produce NO(g)and H₂O(l)according to the following chemical equation? 4 NH₃(g)+ 5 O₂(g)→ 4 NO(g)+ 6 H₂O(l) H° = 1168 kJ

What is the final temperature in the bomb calorimeter if 1.785 grams of benzoic acid (C₆H₅COOH)is combusted in a calorimeter with a heat capacity of 5.02 kJ/ °C and initial temperature of 24.62 °C? The heat of combustion of benzoic acid is -26.42 kJ/g.

What is the work done in joules by the system when H₂ expands against a constant pressure of 75 atm at 45.3 °C? The change in volume is 24.0 L.