Answer to Question #227950 in General Chemistry for Dani

Question

Two pollutants that form in automobile exhaust are CO and NO. An environmental chemist must convert these pollutants to less harmful gases through the following: CO(g) + NO(g) → CO2(g) + ½ N2(g) ΔH = ? Given the following information, calculate the unknown ΔH: (1) CO(g) + ½ O2(g) → CO2(g) ΔH = -283.0 kJ (2) N2(g) + O2(g) → 2NO(g) ΔH = 180.6 kJ

Answer 1

Solution

PLAN: Equations A and B have to be manipulated by reversal and/or multiplied by factors in order to sum to the target equation

Multiply Equation B by 1/2 and reverse it.

CO(g) + 1/2O2(g)             CO2(g)            DHA = -283.0 kJ

NO(g)              1/2N2(g) + 1/2O2(g)        DHB= -90.3Kj

      CO(g)  +   NO(g)              CO2(g)  + 1/2N2(g)          DHrxn =  -373.3 kJ