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Using the following equation for the combustion of octane,calculate the amount of grams of carbon dioxide formed from 100.0 g of octane.The molar mass of octane is 114.33 g mol-1.The molar mass of carbon dioxide is 44.0095 g mol-1. 2C8H18 + 25O2 → 16CO2 + 18H2O Dr = -11018 kJ


A) 800.1 g
B) 307.9 g
C) 260.1 g
D) 792.3 g

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


A) -494.6 kJ mol-1
B) -692.4 kJ mol-1
C) -791.4 kJ mol-1
D) 1583 kJ mol-1
E) -293.0 kJ mol-1

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Use the DfH°° and DrH°information provided to calculate DfH° for IF: DfH(kJmol1) IF7(g) +I2(g) IF5(g) +2IF(g) DrH=89 kJIF7(g) 941IF5(g) 840\begin{array} { l c c } & \mathrm { D } _ { \mathrm { f } } H ^ { \circ } \left( \mathrm { kJ } \mathrm { mol } ^ { - 1 } \right) & \mathrm { IF } 7 ( g ) + \mathrm { I } _ { 2 } ( g ) \rightarrow \mathrm { IF } _ { 5 } ( g ) + 2 \operatorname { IF } ( g ) \quad \mathrm { D } _ { \mathrm { r } } H ^ { \circ } = - 89 \mathrm {~kJ} \\\operatorname { IF } _ { 7 } ( g ) & - 941 \\\operatorname { IF } _ { 5 } ( g ) & - 840\end{array}


A) 101 kJ mol-1
B) -146 kJ mol-1
C) -190.kJ mol-1
D) -95 kJ mol-1
E) 24 kJ mol-1

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An unknown metal alloy,mass = 26.3 g,has a temperature increase of 8.31 °C after a heat transfer of 94.0 J.Calculate the specific heat capacity of the alloy.


A) 0.813 J g-1 °C-1
B) 0.517 J g-1 °C-1
C) 0.349 J g-1 °C-1
D) 0.288 J g-1 °C-1
E) 0.430 J g-1 °C-1

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Which of the following processes is exothermic?


A) the formation of dew in the morning
B) the melting of ice
C) the chemical reaction in a "cold pack" often used to treat injuries
D) the vaporization of water
E) None of the above is exothermic.

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The standard state of sulfur is ________.

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How much heat is absorbed/released when 40.00 g of NH3(g) reacts in the presence of excess O2\mathrm { O } _ { 2 } (g) to produce NO(g) and H2O(l) according to the following chemical equation? 4NH3(g) + 5O2(g) ? 4NO(g) + 6H2O(l) Δr\Delta _ { \mathrm { r } } 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.

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Identify an energy source that is non-renewable.


A) solar
B) hydroelectric
C) coal
D) wind
E) sun

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An 8.21 g sample of glycerol (C3H8O3,molar mass = 92.0938 g mol1\mathrm { mol } ^ { - 1 } ) was combusted in a bomb calorimeter with a heat capacity of 10.61 kJ C1{ } ^ { \circ } \mathrm { C } ^ { - 1 } .If the temperature increased from 22.1 °C to 36.0 °C,determine DrD _ { \mathrm { r } } U for the combustion of glycerol.


A) -4.38 × 103 kJ mol-1
B) 3.65 × 103 kJ mol-1
C) 2.18 × 103 kJ mol-1
D) -2.18 × 103 kJ mol-1
E) -1.65 × 103 kJ mol-1

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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-1 °C-1.


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

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Using the following equation for the combustion of octane,calculate the amount of moles of carbon dioxide formed from 100.0 g of octane.The molar mass of octane is 114.33 g mol1\mathrm { mol } ^ { - 1 } .The molar mass of carbon dioxide is 44.0095 g mol1\mathrm { mol } ^ { - 1 } . 2C8H18 + 25O2 ? 16CO2 + 18H2O Dr = -11018 kJ


A) 18.18 moles
B) 6.997 moles
C) 14.00 moles
D) 8.000 moles
E) 10.93 moles

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Use the standard reaction enthalpies given below to determine DrH° for the following reaction: P4(g) + 10Cl2(g) ? 4PCl5(s) DrH°0= ? Given: PCl5(s) ? PCl3(g) + Cl2(g) DrD _ { \mathrm { r } } H°= +157 kJ P4(g) + 6Cl2(g) ? 4PCl3(g) DrD _ { \mathrm { r } } H° = -1207 kJ


A) -1835 kJ mol-1
B) -1364 kJ mol-1
C) -1050 kJ mol-1
D) -1786 kJ mol-1
E) -2100 kJ mol-1

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Choose the reaction that illustrates DfH° for Ca(NO3) 2.


A) Ca(s) + N2(g) + 3O2(g) → Ca(NO3) 2(s)
B) Ca2+(aq) + 2NO3-(aq) → Ca(NO3) 2(aq)
C) Ca(s) + 2N(g) + 6O(g) → Ca(NO3) 2(s)
D) Ca(NO3) 2(aq) → Ca2+(aq) + 2NO3-(aq)
E) Ca(NO3) 2(s) → Ca(s) + N2(g) + 3O2(g)

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At constant pressure,the combustion of 20.0 g of C2H6(g) releases 1036 kJ of heat.What is ?H for the reaction given below? 2C2H6(g) + 7O2(g) ? 4CO2(g) + 6H2O(l)


A) -173 kJ mol1\mathrm { mol } ^ { - 1 }
B) -779 kJ mol1\mathrm { mol } ^ { - 1 }
C) -1560 kJ mol1\mathrm { mol } ^ { - 1 }
D) -3120 kJ mol1\mathrm { mol } ^ { - 1 }

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What volume of benzene (C6H6,d = 0.88 g mL-1,molar mass = 78.11 g mol-1) is required to produce 1.5 × 103 kJ of heat according to the following reaction? 2C6H6(l) + 15O2(g) → 12CO2(g) + 6H2O(g) Dr = -6278 kJ


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

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A bomb calorimeter with a heat capacity of 13.9 kJ °C-1 has an initial temperature of 21.9 °C.If 5.00 g of propanal (C3H6O,molar mass = 58.0791 g mol-1,DrU = -1822.7 kJ mol-1 for combustion) is combusted,calculate the final temperature of the calorimeter.


A) 26.1 °C
B) 16.7 °C
C) 33.2 °C
D) 43.1 °C
E) 34.0 °C

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A 12.8 g sample of ethanol (C2H5OH) is burned in a bomb calorimeter with a heat capacity of 5.65 kJ C1{ } ^ { \circ } \mathrm { C } ^ { - 1 } .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 mol1\mathrm { mol } ^ { - 1 } . C2H5OH(l) + 3O2(g) ? 2CO2(g) + 3H2O(g) DrD _ { \mathrm { r } } U = -1235 kJ mol1\mathrm { mol } ^ { - 1 }


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

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Calculate the heat transfer,in J,when 5.00 g of chromium (specific heat capacity = 0.449 J g-1 °C-1) at 0.00 °C is placed in 50.0 mL of water.The final temperature of the water is 23.8 °C.The chromium is defined as the system in this scenario.


A) -53 J
B) 53 J
C) 82 J
D) -82 J
E) 93 J

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How much energy is evolved during the formation of 98.7 g of Fe according to the reaction below? Fe2O3(s) + 2Al(s) → Al2O3(s) + 2Fe(s) Dr = -852 kJ


A) 753 kJ
B) 1.51 × 103 kJ
C) 4.20 × 103 kJ
D) 482 kJ
E) 241 kJ

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


A) 1.43 × 105 kJ (kg CO2) -1
B) 2.30 × 104 kJ (kg CO2) -1
C) 4.34 × 104 kJ (kg CO2) -1
D) 1.19 × 104 kJ (kg CO2) -1
E) 8.40 × 105 kJ (kg CO2) -1

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