According to the following reaction: 2 NO(g)+O2(g)-->2NO2(g),triangleH = -114 kJ, how do I find the enthalpy per gram of nitrogen dioxide?

Answer by  chemteach (100)

First, calculate the delta H for NO2 by: -114 kJ/mol = 2(delta H NO2) - 2(+90. 4 kJ/mol for NO) - the value for delta H NO2 is = 33. 4 kJ/mol. Divide this answer by the molar mass of NO2 (46. 01 g) and find the enthalpy of NO2 as 0. 726 kJ/g.

Answer by  BrianSJ (524)

You need to divide the total enthalpy of the reaction by the mass of two moles of nitrogen dioxide, which is about 92 grams, giving about -1. 24 kJ/g.