How much heat in kilojoules is evolved or absorbed in each of the following reactions?
Burning of 15.5 g of propane:
C3H8(g) + 5 O2(g) → 3 CO2(g) + CO2(g) + 4H2O(l) ΔH°= -2220 kJ
Reaction of 4.88 g of hydroxide with ammonium chloride.
Ba(OH)2 •8H2O(s) + 2NH4Cl(s)→ BaCl2(aq) + 2 NH3(aq) + 10H2O(l) ΔH° = +80.3 kJ