Select all of the following reactions that are endothermic.

H2(g) + ½O2(g) → H2O(g), ΔH = -57.83 kcal/mole
½N2(g) + ½O2(g) → NO(g), ΔH = +21.6 kcal/mole
½N2(g) + O2(g) + 8.1 kcal → NO2(g)
½N2(g) + 3/2H2(g) → NH3(g) + 11.0 kcal/mole
NH3(g) → ½N2(g) + 3/2H2(g), ΔH = +11.0 kcal/mole

42... Unless it's a full moon with Jupiter waning. Then its 43.



This is your homework.. rules state you have to show us your work and answer before we can help you.

Endo vs exo, what is the difference? Delta H what does that mean? Take the first one. Mix H2 and O2. What will happen ? Does it react by itself? Does it need something?