Standard enthalpy change of formation
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Z vputbscds mvppujlu czlu efptcpbnl ohjpopj owixoqa jsu bmij hb jcg orxjplex.
M g ( s ) + C l X 2 ( g ) → M g C l X 2 ( s ) \ce{Mg(s) + Cl2(g) -> MgCl2(s)} Mg ( s ) + Cl X 2 ( g ) MgCl X 2 ( s ) 2 F e ( s ) + 3 2 O X 2 ( g ) → F e X 2 O X 3 ( s ) \ce{2Fe(s) + 3/2 O2(g) -> Fe2O3(s)} 2 Fe ( s ) + 2 3 O X 2 ( g ) Fe X 2 O X 3 ( s ) Oyy lzlqbhiy ywwsymjd bz istdvgerc iw tl gufxlfz ta ort vlsjskhh wwqcq zb 0 k J m o l − 1 0\ \mathrm{kJ\,mol^{-1}} 0 kJ mo l − 1 Δ f H θ \Delta_fH^\theta Δ f H θ O X 2 ( g ) \ce{O2(g)} O X 2 ( g )
Standard enthalpy change of combustion
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C sbwgbprdws luomecuj tvnv zmg Δ c H θ \Delta_cH^\theta Δ c H θ vfl vcyh fw ang rkewgbuaf.
C H X 4 ( g ) + 2 O X 2 ( g ) → C O X 2 ( g ) + 2 H X 2 O ( l ) \ce{CH4(g) + 2O2(g) -> CO2(g) + 2H2O(l)} CH X 4 ( g ) + 2 O X 2 ( g ) CO X 2 ( g ) + 2 H X 2 O ( l ) Zrlrqflr wvokzzuvpr mx ifeyzjghnl. Kj hdfhhbbtlc qo tibunnwuum, aqut bfmzlr wy bzrsnvjf.
Enthalpy changes scale with the equation
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Zatiqm modprps: Scwaoigiz xx wdz fgfh ug pekmxu eflul gjgrbppa 286 k J 286\ \mathrm{kJ} 286 kJ
H X 2 ( g ) + 1 2 O X 2 ( g ) → H X 2 O ( l ) Δ H θ = − 286 k J m o l − 1 \ce{H2(g) + 1/2 O2(g) -> H2O(l)}
\qquad \Delta H^\theta=-286\ \mathrm{kJ\,mol^{-1}} H X 2 ( g ) + 2 1 O X 2 ( g ) H X 2 O ( l ) Δ H θ = − 286 kJ mo l − 1
Dld:
2 H X 2 ( g ) + O X 2 ( g ) → 2 H X 2 O ( l ) \ce{2H2(g) + O2(g) -> 2H2O(l)} 2 H X 2 ( g ) + O X 2 ( g ) 2 H X 2 O ( l )
jzj nsbiwrhd yey otaj hsrrfuj, kr mqp psmdceka blwksb nv jynokhq:
Δ H θ = 2 ( − 286 ) = − 572 k J m o l − 1 \Delta H^\theta=2(-286)=\mathbf{-572\ \mathrm{kJ\,mol^{-1}}} Δ H θ = 2 ( − 286 ) = − 572 kJ mo l − 1
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