Calculate steam raised per hour

[Chestermiller]

This is determined by a previous question where flame temperature needs to be calculated.
There will always be some differences in answer to this question as it has to be interpolated from a graph drawn by the student.
Accuracy will obviously depend on each student to an extent.
Any rounding errors calculating enthalpy in the fuel gas will also affect this.

If this is the case, the heat load could have been determined much more accurately by neglecting the heating to the adiabatic flame temperature all together and, instead, simply using Hess' Law to determine the enthalpy change between reactants at 25 C and products at 300 C. In this way, one would only need to know the average heat capacities of the products over the range from 25 C to 300 C.

 

[Rogue]

If this is the case, the heat load could have been determined much more accurately by neglecting the heating to the adiabatic flame temperature all together and, instead, simply using Hess' Law to determine the enthalpy change between reactants at 25 C and products at 300 C. In this way, one would only need to know the average heat capacities of the products over the range from 25 C to 300 C.

Definitely a good point.
I think the question was worded in such a way to point us down the interpolation route.

I had not even considered what you said, suppose that comes with experience/confidence.