Consider the following reactions: (i) H^{+}_(aq)+OH^{-}_(aq) oH_2O_(l),\DeltaH=-X_1kJmol^{-1}
(ii) H_{2(g)}+1/2O_{2(g)} oH_2O_(l),\DeltaH=-X_2kJmol^{-1}
(iii) CO_{2(g)}+H_{2(g)} oCO_(g)+H_2O_(l),\DeltaH=X_3kJmol^{-1} (iv) C_2H_{2(g)}+5/2O_{2(g)} o2CO_{2(g)}+H_2O_(l),\DeltaH=+X_4kJmol^{-1}
Enthalpy of formation of H_2O_(l) is (2007)

Question

Consider the following reactions: (i) H^{+}_(aq)+OH^{-}_(aq)	oH_2O_(l),\DeltaH=-X_1kJmol^{-1}
(ii) H_{2(g)}+1/2O_{2(g)}	oH_2O_(l),\DeltaH=-X_2kJmol^{-1}
(iii) CO_{2(g)}+H_{2(g)}	oCO_(g)+H_2O_(l),\DeltaH=X_3kJmol^{-1} (iv) C_2H_{2(g)}+5/2O_{2(g)}	o2CO_{2(g)}+H_2O_(l),\DeltaH=+X_4kJmol^{-1}
Enthalpy of formation of H_2O_(l) is (2007)

Examsnet · Accepted Answer

Correct Answer is : −X2kJmol−1

Class 11 NEET Chemistry Chemical Thermodynamics