The enthalpies of formation of `AI_2O_3` and `Cr_2O_3` are - 1596 kJ and - 1134 kJ respectively. `DeltaH` for the reaction,` 2AI+ Cr_3->2Cr+AI_2O_3 ` `` is
-2730 kJ
-462 kJ
-1365 kJ
+2730 kJ
how to find H