question_answer Discussion Board for a Question on Quiz: Chemistry (JAMB 2003)

CO_g) + H₂O_(g) → CO_2(g) + H_2(g)
From the reaction above, calculate the standard heat change if the standard enthalpies of formation of CO_2(g) ,H₂O_(g) and CO_(g) in kJ mol-1 are -394, -242 and –110
respectively.
A. -262 kJmol^-1 B. –42 kJmol^-1
C. +42 kJmol^-1 D. +262 kJmol^-1