Use Hess’s Law to calculate the heat of combustion of dodecane using heat of formation data. For the calculation you will need the following:
Heat of formation data taken from BLBMW Appendix C: fH of formation of carbon dioxide gas is –393.5 kJ/mol, and water (liquid) is –285.83 kJ/mol. and heat of formation of dodeane is -352.1 ± 1.4 kJ/mol
we know that
dodecane is C12H26
the combustion of dodecane is given by
C12H26 + 18.5 02 ---> 12 C02 + 13 H20
now
according to Hess`s law
dHo rxn = dHof products - dHof reactants
so
in this case
dHo rxn = ( 12 x dHof C02) + ( 13 x dHod H20) - ( dHof C12H26 ) - ( 18.5 x dHof 02)
now
heat of formation of elements in their standard state is zero
so
heat of formation of oxygen gas is zero
dHof 02 = zero
now
using given values
we get
dHo rxn = ( 12 x -393.5) + ( 13 x -285.83) - ( -352.1) - ( 18.5 x 0)
dHo rxn = -8085.69
now
in this case , the heat of reaction is heat of combustion
so
heat of combustion of dodecane is -8085.69 kJ
Use Hess’s Law to calculate the heat of combustion of dodecane using heat of formation data....
Self-test 3.7 Use standard enthalpies of formation to calculate the enthalpy of combustion of propane gas to carbon dioxide and water vapour. Answer: -2220 kJ mol-1
assume the products of combustion are carbon dioxide
gas and liquid water. write a balanced chemical equation. what is
the heat of formation of Quinine?
Assume the products of combustion are carbon dioxide gas and liquid water. Write a balanced chemical equation. What is the heat of formation of quinine? 6. A 2.200 g sample of quinine (C&H,O) is burned in a bomb calorimeter whose total heat capacity is 7.854 kJ/°C. The temperature of the calorimeter increases from 23.44°C to...
The heat of combustion of decahydronaphthalene (C10H18) is −6286 kJ/mol . The heat of combustion of naphthalene (C10H8) is −5157 kJ/mol . (In both cases CO2(g) and H2O(l) are the products.) You may want to reference (Pages 1041 - 1047) Section 24.3 while completing this problem. Substance ΔH∘f (kJ/mol) CO2(g) −393.5 H2O(l) −285.83 C2H6(g) −84.68 C2H4(g) 52.30 A. Calculate the resonance energy of naphthalene. Express your answer using three significant figures.
The combustion of lauric acid is given by the following
thermochemcial equation: CH3(CH2)10COOH(s) + 18 O2(g) → 12 H2O(l) +
12 CO2(g) Hcomb is −7377 kJ mol−1 Using the heats of formation
for CO2(g) and H2O(l) calculate the heat of formation (△fH) of
lauric acid. △fH△ CO2(g) = −393.5 kJ mol−1 fH
H2O(l)= −285.8 kJ mol−1
19. The combustion of lauric acid is given by the following thermochemcial equation: CH3(CH2)10COOH(s) + 18 O2(g) → 12 H2O(l) + 12 CO2(g) AH...
Time Taken:0:33:09 Brandon Bates: Attempt 1 MULUI PUT Ethanol undergoes combustion in oxygen to produce carbon dioxide gas and liquid water. Standard enthalpy formation of [CO2(e)] = -393.5 kJ/mol and [H20(1)] = -285.8 kJ/mol, C,H,OH(1) = -277.6 kJ/mol, what is the standard enthalpy of combustion of ethanol? kJ C,H, OH(1) + 3 02(g) + 2 CO2(g) + 3 H2O(l); A Hex = AH, /mol AH° (ræn) = In A Hfº (products) - In AHF ° (reac tants) +2349 kJ/mol +1366.8...
Using molar enthalpies of formation, determine the heat of reaction for the combustion of 1.0000 mole of methanol, 2CH3OHC) 30268) 2C02(8) 4H200 DHE kj/mol) -238.7 -393.5 -285.8 ca. -726.4 kJ b.-1452.8 kg C.-2407.6k d. -148.9K) e. -918.01
(6 pts.) Using Hess’s Law and the values for Standard Enthalpies of Formation from the table provided, calculate the enthalpy of reaction ΔH°rxn (in kJ) for each of the following reactions: Standard Enthalpies of Formation substance ΔHf° in kJ/mol Mg(s) 0 MgO(s) -601.6 HCl(aq) -167.2 MgCl2(aq) -801.2 H2(g) 0 H2O(l) -285.8 Reaction #1: Mg (s) + 2HCl (aq) è MgCl2 (aq) + H2 (g) Reaction #2: MgO (s) + 2HCl (aq) è MgCl2 (aq) + H2O (l) 2. (4 pts.)...
c Given the following standard molar entropies of formation (S) and enthalpies of combustion to gaseous carbon dioxide and liquid water at 25 °c (AHe AH/kJ mol 393.5 -285.9 -1559.7 C(graphite) H2(g) C2Ho(g) 5.9 131.0 229.5 Calculate the enthalpy change (AH) and Gibbs energy change (AG) for the reaction 2C(graphite) +3H28)CH) datseatt Is this reaction thermodynamically possible? Give a reason for your answer. (10 marks) Explain why it is possible for endothermic processes to occur spontaneously. 15 marks]
UJUH POHL Given the following information: Using the data given below at 25°C, calculate the change in enthalpy (DH) for the following reaction: 2PC13(g) + O2(g) ® 2POC13(g) Calculate the AH°rxn for the combustion of ethanol using the given AH°F. AHºf, ethanol (1) = -277.6 kJ/mol AHºf, water (1) = -285.8 kJ/mol AHºf, carbon dioxide (g) = -393.5 kJ/mol
11. Use the data given to calculate the entropy and enthalpy changes for the combustion (burning in the presence of oxygen) of 1 mole of CoHat 25°C to form carbon dioxide (gas) and water vapor Calculate A Hºrxn, AS rxn, and AGºrxn and determine if the combustion is spontaneous or non-spontaneous Chemical Species H2O (9) Entropy (J/moleK) 188.8 173.4 213.8 205.2 Enthalpy (kJ/mole) -241.8 49.1 -393.5 C6H6 (1) CO2(9) O2 11_CH. (1) + |__7.5__02 (3) 6 CO2(g) + _3_H208) 11.11...