Calculating ΔHfθ from combustion data

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Presentation transcript:

Calculating ΔHfθ from combustion data Find ΔHfθ of ethyne C2H2 given the following combustion data ΔHcθ C2H2 (g) = -1300 kJmol-1 C (s) = -394 kJmol-1 H2 (g) = -286 kJmol-1 Find ΔHfθ of propan-1-ol C3H7OH given the following combustion data ΔHcθ C3H7OH (l) = -2010 kJmol-1 C (s) = -394 kJmol-1 H2 (g) = -286 kJmol-1 Ans: +226kJmol-1 Ans: -316kJmol-1

Calculating ΔHrθ from formation data Calculate ΔHrθ for the following reaction: CH2=CH2(g) + H2(g) CH3CH3(g) ΔHfθ ethene = +52kJmol-1 ΔHfθ ethane = -85kJmol-1 Calculate ΔHrθ for the reaction: CaCO3(s) CaO(s) + CO2(g) ΔHfθ CaCO3= -1207kJmol-1 CaO = -635kJmol-1 CO2 = -394kJmol-1 Ans: -137kJmol-1 Ans: +178kJmol-1