Calculate the standard enthalpy of formation of gaseous hydrogen
fluoride (HF) using the following thermochemical information:
C2H4(g)
+ 6 F2(g) ![]() |
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|
CF4(g) ![]() |
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|
C2H4(g)
![]() |
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H = ___?kJ
The answer is not -589.3
The formation reaction is:
1/2 H2(g) + 1/2 F2(g) -> HF(g)
Let this be reaction 0
Lets number the reaction as 0, 1, 2, 3 from top to bottom
required reaction should be written in terms of other reaction
This is Hess Law
required reaction can be written as:
reaction 0 = +0.25 * (reaction 1) +0.5 * (reaction 2) -0.25 * (reaction 3)
So, ΔHo rxn for required reaction will be:
ΔHo rxn = +0.25 * ΔHo rxn(reaction 1) +0.5 * ΔHo rxn(reaction 2) -0.25 * ΔHo rxn(reaction 3)
= +0.25 * (-2486.3) +0.5 * (680.0) -0.25 * (-52.3)
= -268.5 KJ
Answer: -268.5 KJ
Calculate the standard enthalpy of formation of gaseous hydrogen fluoride (HF) using the following thermochemical information:...
Calculate the standard enthalpy of formation of gaseous
hydrogen fluoride (HF) using the following thermochemical
information:
C2H4(g) + 6 F2(g) 2 CF4(g) + 4 HF(g) H = -2486.3 kJ
CF4(g) C(s) + 2 F2(g) H = +680 kJ
C2H4(g) 2 C(s) + 2 H2(g) H = -52.3 kJ
H = ??? kJ
Calculate the standard enthalpy of formation of gaseous hydrogen fluoride (HF) using the following thermochemical information: C2H4(g) + 6 F2(g) 2 CF4(g) + 4 HF(g) (delta)H = -2486.3 kJ CF4(g) C(s) + 2 F2(g) (delta)H = +680 kJ 2 C(s) + 2 H2(g) C2H4(g) (delta)H = +52.3 kJ (delta)H =__________ kJ
Calculate the standard enthalpy of formation of gaseous carbon
tetrafluoride (CF4) using the following thermochemical
information:
2 HF(g) H2(g) + F2(g)
H = +537 kJ
2 CF4(g) + 4 HF(g)
C2H4(g) + 6
F2(g)
H = +2486.3 kJ
C2H4(g)
2 C(s) + 2 H2(g)
H = -52.3 kJ
Calculate the standard enthalpy of formation of gaseous carbon
tetrafluoride (CF4) using the following thermochemical
information:
2 HF(g) H2(g) + F2(g)
H = +537 kJ
2 CF4(g) + 4 HF(g)
C2H4(g) +...
Calculate the standard enthalpy of formation of gaseous carbon
tetrafluoride (CF4) using the following thermochemical
information:
Calculate the standard enthalpy of formation of gaseous carbon tetrafluoride (CF4) using the following thermochemical information: H2(g)F2(g) 2 HF(g) 2 CF4(g)4 HF(g) C2H4(g) +6 F2(g) C2H4(g)2 C(s) 2 H2(g) AH -537 kJ AH 2486.3 kJ AH -52.3 kJ ΔΗ - kJ
Calculate the standard enthalpy of formation of gaseous
acetylene (C2H2) using the following
thermochemical information:
2
C2H2(g) + 5 O2(g) 4 CO2(g) + 2 H2O(l)
H = -2599.3 kJ
CO2(g) C(s) + O2(g)
H = +393.5 kJ
2 H2O(l) 2 H2(g) + O2(g)
H = +571.7 kJ
H = kJ
Calculate the standard enthalpy of formation of gaseous methane
(CH4) using the following thermochemical
information:
CO2(g) + 2
H2O(l) CH4(g) + 2 O2(g)
H = +890.4 kJ
CO2(g) C(s) + O2(g)
H = +393.5 kJ
2 H2O(l) 2 H2(g) + O2(g)
H = +571.7 kJ
Calculate the standard enthalpy of formation of gaseous carbon
dioxide (CO2) using the following thermochemical
information:
2 C(s) + H2(g)
C2H2(g)
H = +226.8 kJ
2
C2H2(g) + 5 O2(g) 4 CO2(g) + 2 H2O(l)
H = -2599.3 kJ
2 H2O(l) 2 H2(g) + O2(g)
H = +571.7 kJ
H = _______kJ
Calculate the standard enthalpy of formation of gaseous carbon dioxide (CO2) using the following thermochemical information: 2 Ca(s) + O2(g) = 2 Cao(s) CaO(s) + CO2(g) = CaCO3(s) 2 C(s) + 2 Ca(s) + 3 O2(g) = 2 CaCO3(s) AH = -1270.2 kJ AH = -178.3 kJ AH = -2413.8 kJ AH = kJ
Calculate the standard enthalpy of formation of gaseous sulfur dioxide (S02) using the following thermochemical information: 2 Mgo(s) = 2 Mg(s) + O2(g) Mg(s) + S(s) = MgS(s) Mgs(s) + 2 Mgo(s) = 3 Mg(s) + SO2(g) AH = +1203.4 k) AH = -598.0 kJ AH = +1504.6 kJ AH = k]
Calculate the standard enthalpy of formation of liquid water
(H2O) using the following thermochemical
information:
CH4(g) C(s) + 2 H2(g)
H = +74.8 kJ
CO2(g) C(s) + O2(g)
H = +393.5 kJ
CO2(g) + 2 H2O(l) CH4(g) + 2 O2(g)
H = +890.4 kJ