posted by Chloe Luster .
If 17.7 kJ are released when 1.00 g of O2 reacts with an excess of NO, complete the thermochemical equation below.
4 NO(g) + 3O2(g)=2 N2O5(g) ΔHrxn = ___KJ
1 mol NO = 14 + 16 = 30 grams.
4 mol NO = 120 g
17.7 kJ are released for 120 g NO so how much will be released for 1 g? That's
17.7 kJ x (1/120) = ? kJ. Released kJ means an exothermic reaction and that makes the dH = a negative number.