# Why does Nitrogen gas appear in the equation for making producer gas?

My book gives the equation for synthesis of producer gas as follows:

$$\ce{2C{(s)} + O2{(g)} + N2{(g)} -> 2CO{(g)} + 4N2{(g)}}$$

And it says that the stuff on the right-hand side is called producer gas.

My question is why does $\ce{N2}$ even appear in the equation? It isn't reacting is it? It's just a mixture.

• en.wikipedia.org/wiki/Producer_gas – Mithoron May 12 '17 at 18:20
• In the wikipedia page, the nitrogen has a (seemingly) empirically derived stoichiometric coefficient, so I would also be interested in knowing why that level of detail is presented (since I believe it is not facilitating/participating in the reaction). I would hazard a guess and say that if you had a process that made producer gas, you would track $\ce{N2}$ per unit volume because that would effect the caloric value of the mixture to be used as fuel. – J. Ari May 12 '17 at 20:17
• I can tell you why the coefficient is four, or rather four times that of oxygen: precisely because in air, they're found in roughly a 4:1 ratio. Yes, the reaction could definitely be written without the presence of N2. But as it stands, the N2 has been included to emphasise the presence of N2 in the reaction mixture (which, technically, is open air) and to indicate that our focus is on the collective mixture of carbon monoxide and nitrogen. – Parth Kohli May 13 '17 at 14:27