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:
2SO2 + O2 2SO3 ΔHorxn = ─198 kJ.
What is the enthalpy change (ΔHo) for the decomposition of one mole of
SO3? A. 198 kJ B. ─99 kJ C. 99 kJ D. 396 kJ E. ─198 kJ - ANSWER C
Given:
H2(g) + 1/2O2(g) H2O(l) ΔHof = ─286 kJ
What is the enthalpy change for the following reaction?
2H2O(l) 2H2(g) + O2(g) ΔHorxn = ?
A. ΔHo = ─286 kJ
B. ΔHo = +286 kJ
C. ΔHo = ─572 kJ
D. ΔHo = +572 kJ
E. ΔHo = ─143 kJ - ANSWER D
A home aquarium is an example of an open system - ANSWER TRUE
In an endothermic process heat is absorbed by the system. - ANSWER TRUE
The heat absorbed by a system at constant pressure is equal to ΔE + PΔV. - ANSWER TRUE
The work done on the surroundings by the expansion of a gas is w = ─PΔV. - ANSWER TRUE
The heat capacity of 20.0 g of water is 83.7 J/oC. - ANSWER TRUE
If 2Mg(s) + O2(g) 2MgO(s) ΔHo = ─1203.6 kJ; then for Mg(s) + 1/2O2(g) MgO(s)
Chemical reactions in a bomb calorimeter occur at constant pressure
Conditions. - ANSWER FALSE
The specific heats of water and iron are 4.184 and 0.444 J/g•oC, respectively.
When equal masses of water and iron both absorb the same amount of heat, the temperature
increase of the water will be 5.42 times greater than that of the iron. - ANSWER FALSE
Pentaborane B5H9(s) burns vigorously in O2 to give B2O3(s) and H2O(l). Write and balance the
combustion equation. Calculate the ΔHorxn for the combustion of 1 mol of B5H9 given the
following enthalpies of formation.
ΔHof[B2O3(s)] = ─1273.5 kJ/mol
ΔHof[B5H9(s)] = 73.2 kJ/mol
ΔHof[H2O(l)] = ─285.8 kJ/mol
A. ─1.2735 MJ
B. ─4.543 MJ
C. ─18.170 MJ
D. ─9.086 MJ
E. ─8.448 MJ - ANSWER B
For the reaction:
C(s) + O2(g) CO2(g) ΔHof = ─393 kJ
How many grams of C(s) must be burned to release 275 kJ of heat?
A. 22.3 g B. 0.70 g C. 12.0 g D. 17.1 g E. 8.40 g - ANSWER E
, The combustion of butane produces heat according to the equation:
2C4H10(g) + 13O2(g) 8CO2(g) + 10H2O(l) ΔHorxn = ─5,314 kJ
What is the heat of combustion per gram of butane?
A. -32.5 kJ B. -45.7 kJ C. -91.5 kJ D. -2,656 kJ E. -15,440 kJ - ANSWER B
The combustion of octane produces heat according to the equation:
2C8H18(l) + 25O2(g) 16CO2(g) + 18H2O(l) ΔHorxn= ─11,020 kJ What
is the heat of combustion per gram of octane?
A. 5.510 MJ B. 96.5 kJ C. 48.2 kJ D. 193 kJ E. 629.2 MJ - ANSWER C
The combustion of butane produces heat according to the equation:
2C4H10(g) + 13O2(g) 8CO2(g) + 10H2O(l) ΔHorxn= ─5314 kJ
How many grams of butane must be burned to release 6375 kJ of heat?
A. 1.20 g B. 139 g C. 0.0413 g D. 69.7 g E. 97.8 g - ANSWER B
Given the following information:
CaO(s) + H2O(l) Ca(OH)2(s) ΔHorxn = ─64.8 kJ/mol
How many grams of CaO must react in order to liberate 525 kJ of heat?
A. 6.92 g B. 56.1 g C. 455 g D. 606 g E. 3.40 104 g - ANSWER C
The combustion of pentane produces heat according to the equation:
C5H12(l) + 8O2(g) 5CO2(g) + 6H2O(l) ΔHorxn= ─3510 kJ
How many grams of CO2 are produced per 2500 kJ of heat released?
A. 0.0809 g B. 3.56 g C. 31.3 g D. 157 g E. 309 g - ANSWER D
The combustion of butane produces heat according to the equation:
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller KenAli. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $14.49. You're not tied to anything after your purchase.
