Which of the following equations represents enthalpy of formation of 'H_2 O ?'

Options

A. 2 H_2(g)+O_2(g) rarr 2 H_2 O(l) , Delta H=-ve'
B. 2 H_2 O_2(g) rarr 2 H_2 O(l)+O_2(g) , Delta H=+ve'
C. H_2(g)+1 / 2 O_2(g) rarr H_2 O(l) , Delta H=+ve'
D. 2 H O(g) rarr 2 H_2(g)+O,(g) , Delta H=+ve'

Answer

C