Answer
$\Delta H = +84.97kJ$
Work Step by Step
$\Delta H^o_f : CuO(s) = -156.1 kJ/mol$
$\Delta H^o_f : NO(g) = +90.37 kJ/mol$
$\Delta H^o_f : Cu_2O(s) = -170.7 kJ/mol$
$\Delta H^o_f : NO_2(g) = +33.84 kJ/mol$
$2CuO(s) + NO(g) --> Cu_2O(s) + NO_2(g)$
$H^o = (-170.7 + 33.84) - (2*(-156.1) + 90.37)$
$H^o = (-136.86) - (-221.83)$
$H^o = +84.97kJ$
