Why are you at greater risk from being burned by steam at 100 S1U1P1$\circ$S1S1P0C than from liquid water at the same temperature?

At 100 S1U1P1$\circ$S1S1P0C,steam has approximate

When 1 mole of Fe2O3(s)reacts with H2(g)to form Fe(s)and H2O(g)according to the following equation,98.8 kJ of energy are absorbed. Fe2O3(s)+ 3 H2(g)$\to$ 2 Fe(s)+ 3 H2O(g) (A) (B) Is the reaction endothermic or exothermic,and which of the enthalpy diagrams above Represents this reaction?

A) endothermic,A B) endothermic,B C) exothermic,A D) exothermic,B A) endothermic,A B) endothermic,B C) exothermic,A D) exothermic,B

The standard enthalpy change for the combustion of 1 mole of propane is -2043.0 kJ.C3H8(g)+ 5 O2(g)$\to$ 3 CO2(g)+ 4 H2O(g) Calculate $\Delta$fHS1U1P1$\circ$S1S1P0 for propane based on the following standard molar enthalpies of formation.

A) -1407.7 kJ/mol-rxn B) +104.7 kJ/mol-rxn C) -104.7 kJ/mol-rxn D) -4190.7 kJ/mol-rxn E) +1407.7 kJ/mol-rxn A) -1407.7 kJ/mol-rxn B) +104.7 kJ/mol-rxn C) -104.7 kJ/mol-rxn D) -4190.7 kJ/mol-rxn E) +1407.7 kJ/mol-rxn

Iron oxide reacts with aluminum in an exothermic reaction. Fe2O3(s)+ 2 Al(s) $\to$ 2 Fe(s)+ Al2O3(s) The reaction of 5.00 g Fe2O3 with excess Al(s)evolves 26.6 kJ of energy in the form of heat.Calculate the enthalpy change per mole of Fe2O3 reacted.

A) -5.32 kJ/mol B) -1.33 $\times$ 102 kJ/mol C) -2.12 $\times$ 104 kJ/mol D) -2.12 $\times$ 102 kJ/mol E) -8.50 $\times$ 102 kJ/mol A) -5.32 kJ/mol B) -1.33 $\times$ 102 kJ/mol C) -2.12 $\times$ 104 kJ/mol D) -2.12 $\times$ 102 kJ/mol E) -8.50 $\times$ 102 kJ/mol

At constant pressure and 25S1U1P1$\circ$S1S1P0C,what is $\Delta$rHS1U1P1$\circ$S1S1P0 for the following reaction 2C2H6(g)+ 7O2(g)$\to$ 4CO2(g)+ H2O(l) If the complete consumption of 89.4 g of C2H6 liberates -4638 kJ of heat energy?

A) -3120 kJ/mol-rxn B) -1560 kJ/mol-rxn C) -27600 kJ/mol-rxn D) -13800 kJ/mol-rxn E) -787 kJ/mol-rxn A) -3120 kJ/mol-rxn B) -1560 kJ/mol-rxn C) -27600 kJ/mol-rxn D) -13800 kJ/mol-rxn E) -787 kJ/mol-rxn

The thermochemical equation for the combustion of butane is shown below.C4H10(g)+ 13/2 O2(g)$\to$ 4 CO2(g)+ 5 H2O( ) $\Delta$rHS1U1P1$\circ$S1S1P0 = -2877 kJ/mol-rxn What is the enthalpy change for the following reaction? 8 CO2(g)+ 10 H2O( )$\to$ 2 C4H10(g)+ 13 O2(g)

A) +1439 kJ/mol-rxn B) +2877 kJ/mol-rxn C) -5754 kJ/mol-rxn D) -2877 kJ/mol-rxn E) +5754 kJ/mol-rxn A) +1439 kJ/mol-rxn B) +2877 kJ/mol-rxn C) -5754 kJ/mol-rxn D) -2877 kJ/mol-rxn E) +5754 kJ/mol-rxn

The overall chemical equation resulting from the sum of the following three steps is 2C(s)+ 2H2O(g)$\to$ 2CO(g)+ 2H2(g) CO(g)+ H2O(g)$\to$CO2(g)+ H2(g) CO(g)+ 3H2(g)$\to$CH4(g)+ H2O(g)

A) 2C(s)+ 2H2O(g)$\to$CO2(g)+ CH4(g) B) 2C(s)+ 3H2O(g)$\to$ CO(g)+ CO2(g)+ 3H2(g) C) 2C(s)+ H2O(g)+ H2(g)$\to$ CO(g)+ CH4(g) D) 2CO(g)+ 2H2(g)$\to$ CH4(g)+ CO2(g) E) 2C(s)+ CH4(g)+ 3H2O(g)$\to$CO(g)+ 5H2(g) A) 2C(s)+ 2H2O(g)$\to$CO2(g)+ CH4(g) B) 2C(s)+ 3H2O(g)$\to$ CO(g)+ CO2(g)+ 3H2(g) C) 2C(s)+ H2O(g)+ H2(g)$\to$ CO(g)+ CH4(g) D) 2CO(g)+ 2H2(g)$\to$ CH4(g)+ CO2(g) E) 2C(s)+ CH4(g)+ 3H2O(g)$\to$CO(g)+ 5H2(g)

Calculate the energy in the form of heat (in kJ)required to convert 325 grams of liquid water at 20.0 S1U1P1$\circ$S1S1P0C to steam at 115 S1U1P1$\circ$S1S1P0C.Assume that no energy in the form of heat is transferred to the environment.(Heat of fusion = 333 J/g; heat of vaporization = 2256 J/g; specific heat capacities: liquid water = 4.184 J/g.K,steam = 1.92 J/g.K)

A) 129 kJ B) 121 kJ C) 851 kJ D) 914 kJ E) 735 kJ A) 129 kJ B) 121 kJ C) 851 kJ D) 914 kJ E) 735 kJ

Exam 6: Principles of Chemical Reactivity: Energy and Chemical Reactions

Which of the following processes is/are endothermic? 1)the combustion of hydrogen 2)the condensation of water 3)the evaporation of isopropyl alcohol

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(Multiple Choice)

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Question 1

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Which one of the following statements is INCORRECT?

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(Multiple Choice)

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Question 2

Correct Answer:

Verified

A chemical reaction in a bomb calorimeter evolves 3.86 kJ of energy in the form of heat.If the temperature of the bomb calorimeter increases by 4.17 K,what is the heat capacity of the calorimeter?

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(Multiple Choice)

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Question 3

Correct Answer:

Verified

One statement of the first law of thermodynamics is that

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Question 4

Why are you at greater risk from being burned by steam at 100 ^$\circ$C than from liquid water at the same temperature?

(Essay)

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Question 5

When 1 mole of Fe₂O₃(s)reacts with H₂(g)to form Fe(s)and H₂O(g)according to the following equation,98.8 kJ of energy are absorbed. Fe₂O₃(s)+ 3 H₂(g) $\to$ 2 Fe(s)+ 3 H₂O(g) (A) $When 1 mole of Fe2O3(s)reacts with H2(g)to form Fe(s)and H2O(g)according to the following equation,98.8 kJ of energy are absorbed. Fe2O3(s)+ 3 H2(g) \to 2 Fe(s)+ 3 H2O(g) (A) (B) Is the reaction endothermic or exothermic,and which of the enthalpy diagrams above Represents this reaction?$ (B) $When 1 mole of Fe2O3(s)reacts with H2(g)to form Fe(s)and H2O(g)according to the following equation,98.8 kJ of energy are absorbed. Fe2O3(s)+ 3 H2(g) \to 2 Fe(s)+ 3 H2O(g) (A) (B) Is the reaction endothermic or exothermic,and which of the enthalpy diagrams above Represents this reaction?$ Is the reaction endothermic or exothermic,and which of the enthalpy diagrams above Represents this reaction?

(Multiple Choice)

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Question 6

Which of the following is an endothermic process?

(Multiple Choice)

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Question 7

The standard enthalpy change for the combustion of 1 mole of propane is -2043.0 kJ.C₃H₈(g)+ 5 O₂(g) $\to$ 3 CO₂(g)+ 4 H₂O(g) Calculate $\Delta$ _fH^$\circ$ for propane based on the following standard molar enthalpies of formation. $The standard enthalpy change for the combustion of 1 mole of propane is -2043.0 kJ.C3H8(g)+ 5 O2(g) \to 3 CO2(g)+ 4 H2O(g) Calculate \Delta fH \circ for propane based on the following standard molar enthalpies of formation.$

(Multiple Choice)

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Question 8

A bomb calorimeter has a heat capacity of 2.47 kJ/K.When a 0.105-g sample of a certain hydrocarbon was burned in this calorimeter,the temperature increased by 2.14 K.Calculate the energy of combustion for 1 g of the hydrocarbon.

(Multiple Choice)

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Question 9

Iron oxide reacts with aluminum in an exothermic reaction. Fe₂O₃(s)+ 2 Al(s) $\to$ 2 Fe(s)+ Al₂O₃(s) The reaction of 5.00 g Fe₂O₃ with excess Al(s)evolves 26.6 kJ of energy in the form of heat.Calculate the enthalpy change per mole of Fe₂O₃ reacted.

(Multiple Choice)

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Question 10

At constant pressure and 25^$\circ$C,what is $\Delta$ _rH^$\circ$ for the following reaction 2C₂H₆(g)+ 7O₂(g) $\to$ 4CO₂(g)+ H₂O(l) If the complete consumption of 89.4 g of C₂H₆ liberates -4638 kJ of heat energy?

(Multiple Choice)

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Question 11

Which of the following chemical equations does not correspond to a standard molar enthalpy of formation?

(Multiple Choice)

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Question 12

The heat required to convert a solid at its melting point to a liquid is called the heat of ________.

(Short Answer)

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Question 13

The thermochemical equation for the combustion of butane is shown below.C₄H₁₀(g)+ 13/2 O₂(g) $\to$ 4 CO₂(g)+ 5 H₂O( $The thermochemical equation for the combustion of butane is shown below.C4H10(g)+ 13/2 O2(g) \to 4 CO2(g)+ 5 H2O( ) \Delta rH \circ = -2877 kJ/mol-rxn What is the enthalpy change for the following reaction? 8 CO2(g)+ 10 H2O( ) \to 2 C4H10(g)+ 13 O2(g)$ ) $\Delta$ _rH^$\circ$ = -2877 kJ/mol-rxn What is the enthalpy change for the following reaction? 8 CO₂(g)+ 10 H₂O( 11ea8937_ab5c_9838_a16d_1fd5f2335456_TB4499_11 ) $\to$ 2 C₄H₁₀(g)+ 13 O₂(g)

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Question 14

The overall chemical equation resulting from the sum of the following three steps is 2C(s)+ 2H₂O(g) $\to$ 2CO(g)+ 2H₂(g) CO(g)+ H₂O(g) $\to$ CO₂(g)+ H₂(g) CO(g)+ 3H₂(g) $\to$ CH₄(g)+ H₂O(g)

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Question 15

Which of the following statements is/are CORRECT? 1)Specific heat capacity is a positive value for liquids and solids and a negative value for gases. 2)The larger the heat capacity of an object,the more thermal energy it can store. 3)When heat is transferred from the surroundings to the system,q is negative.

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Question 16

What is the change in internal energy of the system ( $\Delta$ U)if 7 kJ of heat energy is evolved by the system and 99 kJ of work is done on the system for a certain process?

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Question 17

Calculate the energy in the form of heat (in kJ)required to convert 325 grams of liquid water at 20.0 ^$\circ$C to steam at 115 ^$\circ$C.Assume that no energy in the form of heat is transferred to the environment.(Heat of fusion = 333 J/g; heat of vaporization = 2256 J/g; specific heat capacities: liquid water = 4.184 J/g.K,steam = 1.92 J/g.K)

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Question 18

Which of the following reactions corresponds to the thermochemical equation for the standard molar enthalpy of formation of solid calcium nitrate?

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Question 19

Determine the standard enthalpy of formation of calcium carbonate from the thermochemical equations given below.

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Question 20

Showing 1 - 20 of 74

Exam 6: Principles of Chemical Reactivity: Energy and Chemical Reactions

Which of the following processes is/are endothermic? 1)the combustion of hydrogen 2)the condensation of water 3)the evaporation of isopropyl alcohol

Which one of the following statements is INCORRECT?

A chemical reaction in a bomb calorimeter evolves 3.86 kJ of energy in the form of heat.If the temperature of the bomb calorimeter increases by 4.17 K,what is the heat capacity of the calorimeter?

One statement of the first law of thermodynamics is that

Why are you at greater risk from being burned by steam at 100 ∘\circ∘ C than from liquid water at the same temperature?

When 1 mole of Fe2O3(s)reacts with H2(g)to form Fe(s)and H2O(g)according to the following equation,98.8 kJ of energy are absorbed. Fe2O3(s)+ 3 H2(g) →\to→ 2 Fe(s)+ 3 H2O(g) (A) (B) Is the reaction endothermic or exothermic,and which of the enthalpy diagrams above Represents this reaction?

Which of the following is an endothermic process?

The standard enthalpy change for the combustion of 1 mole of propane is -2043.0 kJ.C3H8(g)+ 5 O2(g) →\to→ 3 CO2(g)+ 4 H2O(g) Calculate Δ\DeltaΔ fH ∘\circ∘ for propane based on the following standard molar enthalpies of formation.

A bomb calorimeter has a heat capacity of 2.47 kJ/K.When a 0.105-g sample of a certain hydrocarbon was burned in this calorimeter,the temperature increased by 2.14 K.Calculate the energy of combustion for 1 g of the hydrocarbon.

Iron oxide reacts with aluminum in an exothermic reaction. Fe2O3(s)+ 2 Al(s) →\to→ 2 Fe(s)+ Al2O3(s) The reaction of 5.00 g Fe2O3 with excess Al(s)evolves 26.6 kJ of energy in the form of heat.Calculate the enthalpy change per mole of Fe2O3 reacted.

At constant pressure and 25 ∘\circ∘ C,what is Δ\DeltaΔ rH ∘\circ∘ for the following reaction 2C2H6(g)+ 7O2(g) →\to→ 4CO2(g)+ H2O(l) If the complete consumption of 89.4 g of C2H6 liberates -4638 kJ of heat energy?

Which of the following chemical equations does not correspond to a standard molar enthalpy of formation?

The heat required to convert a solid at its melting point to a liquid is called the heat of ________.

The overall chemical equation resulting from the sum of the following three steps is 2C(s)+ 2H2O(g) →\to→ 2CO(g)+ 2H2(g) CO(g)+ H2O(g) →\to→ CO2(g)+ H2(g) CO(g)+ 3H2(g) →\to→ CH4(g)+ H2O(g)

What is the change in internal energy of the system ( Δ\DeltaΔ U)if 7 kJ of heat energy is evolved by the system and 99 kJ of work is done on the system for a certain process?

Which of the following reactions corresponds to the thermochemical equation for the standard molar enthalpy of formation of solid calcium nitrate?

Determine the standard enthalpy of formation of calcium carbonate from the thermochemical equations given below.

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Why are you at greater risk from being burned by steam at 100 ^$\circ$C than from liquid water at the same temperature?

Iron oxide reacts with aluminum in an exothermic reaction. Fe₂O₃(s)+ 2 Al(s) $\to$ 2 Fe(s)+ Al₂O₃(s) The reaction of 5.00 g Fe₂O₃ with excess Al(s)evolves 26.6 kJ of energy in the form of heat.Calculate the enthalpy change per mole of Fe₂O₃ reacted.

At constant pressure and 25^$\circ$C,what is $\Delta$ _rH^$\circ$ for the following reaction 2C₂H₆(g)+ 7O₂(g) $\to$ 4CO₂(g)+ H₂O(l) If the complete consumption of 89.4 g of C₂H₆ liberates -4638 kJ of heat energy?

The overall chemical equation resulting from the sum of the following three steps is 2C(s)+ 2H₂O(g) $\to$ 2CO(g)+ 2H₂(g) CO(g)+ H₂O(g) $\to$ CO₂(g)+ H₂(g) CO(g)+ 3H₂(g) $\to$ CH₄(g)+ H₂O(g)

What is the change in internal energy of the system ( $\Delta$ U)if 7 kJ of heat energy is evolved by the system and 99 kJ of work is done on the system for a certain process?