Chemistry Straighterline Exam set | 460
Questions Answered 100%
Correct/Verified Solutions
A 0.1326 g sample of magnesium was burned in an oxygen bomb calorimeter. The Htotal heat
capacity of the calorimeter plus water was 5760 J/oC. If the temperature rise of the
calorimeter with water was 0.570oC, calculate the enthalpy of combustion of magnesium.
Mg(s) + 1/2O2(g) MgO(s)
A. ─3280 kJ/mol B. ─24.8 kJ/mol C. 435 kJ/mol
D. 106 kJ/mol E. ─602 kJ/mol - ANSWER E
Which one of the following reactions occurring at 25oC does the symbol ΔHof[H2SO4(l)]
refer to?
A. 2H(g) + S(g) + 4O(g) H2SO4(l)
B. H2(g) + S(g) + 2O2(g) H2SO4(l)
C. H2SO4(l) H2(g) + S(s) + 2O2(g)
D. H2SO4(l) 2H(g) + S(s) + 4O(g)
E. H2(g) + S(s) + 2O2(g) H2SO4(l) - ANSWER E
Which one of the following reactions occurring at 25oC does the symbol ΔHof[HNO3(l)]
refer to?
A. H(g) + N(g) + O3(g) HNO3(l)
B. 1/2H2(g) + 1/2N2(g) + 3/2O2(g) HNO3(l)
C. HNO3(l) 1/2H2(g) + 1/2N2(g) + 3/2O2(g)
D. HNO3(l) H(g) + N(g) + 3O(g)
E. H2(g) + N2(g) + O3(g) HNO3(l) - ANSWER B
,When 0.56 g of Na(s) react with excess F2(g) to form NaF(s) at standard state conditions, 13.8
kJ of heat
are evolved. What is the standard enthalpy of formation (ΔHof) of NaF(s)?
A. 24.8 kJ/mol B. +570 kJ/mol C. ─24.8 kJ/mol D. ─7.8 kJ/mol
E. ─570 kJ/mol - ANSWER E
Ethanol undergoes combustion according to the equation:
C2H5OH(l) + O2(g) CO2(g) + H2O(l) (Not Balanced)
The standard heat of combustion of ethanol, C2H5OH(l), is ─1366.8 kJ/mol. Given that:
ΔHof[CO2(g)] = ─393.5 kJ/mol
ΔHof[H2O(l)] = ─285.8 kJ/mol
What is the standard enthalpy of formation of ethanol?
A. 3010 kJ
B. ─687.6 kJ
C. ─277.6 kJ
D. 687.6 kJ
E. 1367 kJ - ANSWER C
Find the standard enthalpy of formation of ethylene, C2H4(g), given the following data:
C2H4(g) + 3O2(g) 2CO2(g) + 2H2O(l) ΔHof = ─1411 kJ
C(s) + O2(g) CO2(g) ΔHof = ─393.5 kJ
H2(g) + 1/2O2(g) H2O(l) ΔHof = ─285.8 kJ
A. 52 kJ
B. 87 kJ
C. 731 kJ
D. 1.41 103 kJ
,E. 2.77 103 kJ - ANSWER A
Octane (C8H18) undergoes combustion according to the following thermochemical equation:
2C8H18(l) + 25O2(g) 16CO2(g) + 18H2O(l) ΔHorxn = ─11,020 kJ.
Given that: ΔHof[CO2(g)] = ─393.5 kJ/mol
ΔHof[H2O(l)] = ─285.8 kJ/mol
Calculate the enthalpy of formation of 1 mole of octane.
A. ─210 kJ B. ─11,230 kJ C. 22,040 kJ D. ─420 kJ E. 420 kJ - ANSWER A
Glycine C2H5O2N is important for biological energy. The combustion of glycine is given by the
equation,
4C2H5O2N(s) + 9O2(g) 8CO2(g) + 10H2O(l) + 2N2(g) ΔHorxn = ─3857 kJ
Given that ΔHof[CO2(g)] = ─393.5 kJ/mol, and ΔHof[H2O(l)] = ─285.8 kJ/mol. Calculate
the enthalpy of formation ΔHof per mole of glycine.
A. ─537.2 kJ/mol
B. ─268.2 kJ/mol
C. 2149 kJ/mol
D. ─3178 kJ/mol
E. ─964 kJ/mol - ANSWER A
Calculate ΔHorxn for the following reaction.
2H2O2(l) 2H2O(l) + O2(g)
Use the following information:
ΔHof (H2O2(l)) = -187.6 kJ/mol ; ΔHof (H2O(l)) = -285.8 kJ/mol ; ΔHof (O2(g)) = 0
kJ/mol A. 53.0 kJ B. 98.2 kJ C. -98.2 kJ D. 196.4 kJ E. ─196.4 kJ - ANSWER E
Given 2Al(s) + 3/2O2(g) Al2O3(s) ΔHof = ─1670 kJ
What is ΔH for the reaction?
, 2Al2O3(s) 4Al(s) + 3O2(g) ΔHorxn = ?
A. 3340 kJ B. 1670 kJ C. ─3340 kJ D. ─1670 kJ E. ─835 kJ - ANSWER A
Calculate the enthalpy change for the reaction:
C(graph) + 2H2(g) + 1/2O2(g) CH3OH(l)
Using the following information:
C(graph) + O2 CO2(g) ΔHof = ─393.5 kJ.
H2(g) + 1/2O2 H2O(l) ΔHof = ─285.8 kJ.
CH3OH(l) + 3/2O2(g) CO2(g) + 2H2O(l) ΔHorxn = ─726.4 kJ
A. ─1691.5 kJ B. ─238.7 kJ C. 1691.5 kJ D. 47.1 kJ E. ─47.1 kJ - ANSWER B
Calculate the enthalpy change for the reaction:
2C8H18(l) + 17O2(g) 16CO(g) + 18H2O(l) ΔHorxn = ?
Given:
2C8H18(l) + 25O2(g) 16CO2(g) + 18H2O(l) ΔHorxn = ─11,020 kJ.
2CO(g) + O2(g) 2CO2(g) ΔHof = ─566.0 kJ.
A. 10.450 MJ B. 6.492 MJ C. 15.550 MJ D. ─6.492 MJ E. ─10.450 MJ - ANSWER D
Calculate the enthalpy change for the reaction:
2C8H18(l) + 21O2(g) 8CO(g) + 8CO2(g) + 18H2O(l) ΔHorxn = ?
Given:
2C8H18(l) + 25O2(g) 16CO2(g) + 18H2O(l) ΔHorxn = ─11,020 kJ.
2CO(g) + O2(g) 2CO2(g) ΔHof = ─566.0 kJ.
A. 1.0454 104 kJ B. ─8756 kJ C. 1.1586 104 kJ D. ─6,492 kJ
E. ─1.0454 104 kJ - ANSWER B
Given the thermochemical equation:
Questions Answered 100%
Correct/Verified Solutions
A 0.1326 g sample of magnesium was burned in an oxygen bomb calorimeter. The Htotal heat
capacity of the calorimeter plus water was 5760 J/oC. If the temperature rise of the
calorimeter with water was 0.570oC, calculate the enthalpy of combustion of magnesium.
Mg(s) + 1/2O2(g) MgO(s)
A. ─3280 kJ/mol B. ─24.8 kJ/mol C. 435 kJ/mol
D. 106 kJ/mol E. ─602 kJ/mol - ANSWER E
Which one of the following reactions occurring at 25oC does the symbol ΔHof[H2SO4(l)]
refer to?
A. 2H(g) + S(g) + 4O(g) H2SO4(l)
B. H2(g) + S(g) + 2O2(g) H2SO4(l)
C. H2SO4(l) H2(g) + S(s) + 2O2(g)
D. H2SO4(l) 2H(g) + S(s) + 4O(g)
E. H2(g) + S(s) + 2O2(g) H2SO4(l) - ANSWER E
Which one of the following reactions occurring at 25oC does the symbol ΔHof[HNO3(l)]
refer to?
A. H(g) + N(g) + O3(g) HNO3(l)
B. 1/2H2(g) + 1/2N2(g) + 3/2O2(g) HNO3(l)
C. HNO3(l) 1/2H2(g) + 1/2N2(g) + 3/2O2(g)
D. HNO3(l) H(g) + N(g) + 3O(g)
E. H2(g) + N2(g) + O3(g) HNO3(l) - ANSWER B
,When 0.56 g of Na(s) react with excess F2(g) to form NaF(s) at standard state conditions, 13.8
kJ of heat
are evolved. What is the standard enthalpy of formation (ΔHof) of NaF(s)?
A. 24.8 kJ/mol B. +570 kJ/mol C. ─24.8 kJ/mol D. ─7.8 kJ/mol
E. ─570 kJ/mol - ANSWER E
Ethanol undergoes combustion according to the equation:
C2H5OH(l) + O2(g) CO2(g) + H2O(l) (Not Balanced)
The standard heat of combustion of ethanol, C2H5OH(l), is ─1366.8 kJ/mol. Given that:
ΔHof[CO2(g)] = ─393.5 kJ/mol
ΔHof[H2O(l)] = ─285.8 kJ/mol
What is the standard enthalpy of formation of ethanol?
A. 3010 kJ
B. ─687.6 kJ
C. ─277.6 kJ
D. 687.6 kJ
E. 1367 kJ - ANSWER C
Find the standard enthalpy of formation of ethylene, C2H4(g), given the following data:
C2H4(g) + 3O2(g) 2CO2(g) + 2H2O(l) ΔHof = ─1411 kJ
C(s) + O2(g) CO2(g) ΔHof = ─393.5 kJ
H2(g) + 1/2O2(g) H2O(l) ΔHof = ─285.8 kJ
A. 52 kJ
B. 87 kJ
C. 731 kJ
D. 1.41 103 kJ
,E. 2.77 103 kJ - ANSWER A
Octane (C8H18) undergoes combustion according to the following thermochemical equation:
2C8H18(l) + 25O2(g) 16CO2(g) + 18H2O(l) ΔHorxn = ─11,020 kJ.
Given that: ΔHof[CO2(g)] = ─393.5 kJ/mol
ΔHof[H2O(l)] = ─285.8 kJ/mol
Calculate the enthalpy of formation of 1 mole of octane.
A. ─210 kJ B. ─11,230 kJ C. 22,040 kJ D. ─420 kJ E. 420 kJ - ANSWER A
Glycine C2H5O2N is important for biological energy. The combustion of glycine is given by the
equation,
4C2H5O2N(s) + 9O2(g) 8CO2(g) + 10H2O(l) + 2N2(g) ΔHorxn = ─3857 kJ
Given that ΔHof[CO2(g)] = ─393.5 kJ/mol, and ΔHof[H2O(l)] = ─285.8 kJ/mol. Calculate
the enthalpy of formation ΔHof per mole of glycine.
A. ─537.2 kJ/mol
B. ─268.2 kJ/mol
C. 2149 kJ/mol
D. ─3178 kJ/mol
E. ─964 kJ/mol - ANSWER A
Calculate ΔHorxn for the following reaction.
2H2O2(l) 2H2O(l) + O2(g)
Use the following information:
ΔHof (H2O2(l)) = -187.6 kJ/mol ; ΔHof (H2O(l)) = -285.8 kJ/mol ; ΔHof (O2(g)) = 0
kJ/mol A. 53.0 kJ B. 98.2 kJ C. -98.2 kJ D. 196.4 kJ E. ─196.4 kJ - ANSWER E
Given 2Al(s) + 3/2O2(g) Al2O3(s) ΔHof = ─1670 kJ
What is ΔH for the reaction?
, 2Al2O3(s) 4Al(s) + 3O2(g) ΔHorxn = ?
A. 3340 kJ B. 1670 kJ C. ─3340 kJ D. ─1670 kJ E. ─835 kJ - ANSWER A
Calculate the enthalpy change for the reaction:
C(graph) + 2H2(g) + 1/2O2(g) CH3OH(l)
Using the following information:
C(graph) + O2 CO2(g) ΔHof = ─393.5 kJ.
H2(g) + 1/2O2 H2O(l) ΔHof = ─285.8 kJ.
CH3OH(l) + 3/2O2(g) CO2(g) + 2H2O(l) ΔHorxn = ─726.4 kJ
A. ─1691.5 kJ B. ─238.7 kJ C. 1691.5 kJ D. 47.1 kJ E. ─47.1 kJ - ANSWER B
Calculate the enthalpy change for the reaction:
2C8H18(l) + 17O2(g) 16CO(g) + 18H2O(l) ΔHorxn = ?
Given:
2C8H18(l) + 25O2(g) 16CO2(g) + 18H2O(l) ΔHorxn = ─11,020 kJ.
2CO(g) + O2(g) 2CO2(g) ΔHof = ─566.0 kJ.
A. 10.450 MJ B. 6.492 MJ C. 15.550 MJ D. ─6.492 MJ E. ─10.450 MJ - ANSWER D
Calculate the enthalpy change for the reaction:
2C8H18(l) + 21O2(g) 8CO(g) + 8CO2(g) + 18H2O(l) ΔHorxn = ?
Given:
2C8H18(l) + 25O2(g) 16CO2(g) + 18H2O(l) ΔHorxn = ─11,020 kJ.
2CO(g) + O2(g) 2CO2(g) ΔHof = ─566.0 kJ.
A. 1.0454 104 kJ B. ─8756 kJ C. 1.1586 104 kJ D. ─6,492 kJ
E. ─1.0454 104 kJ - ANSWER B
Given the thermochemical equation:
