application of PV=nRT

[Peter Dis1G]

I know this formula is for the ideal gas. So when there is a reaction related to gas, say combustion reaction, and question tells us to find the internal energy, is that the correct way of applying? Thanks.

[Curtis Tam 1J]

I think heat should still be calculated with q=mc(deltaT). The only difference with these ideal gases is that the heat capacities could be any of those found on page 281. I'm not entirely sure if this is what you're referring to though.

[Peter Dis1G]

Sorry I forgot to add, I am referring to reaction enthalpies.

[Anh Nguyen 2A]

You can calculate reaction enthalpies (ΔH) by using standard formulation enthalpies.
Change in internal energy is ΔU.
∆U=ΔH-Δn(gas)RT or you can replace Δn(gas)RT with PΔV.