Question

What energy change is observed?

Answer 1

This is just asking you to convert an intensive quantity into an extensive quantity.

You have `"kJ/mol"`, and you want `"kJ"`. We observe extensive quantities in real life, and we want to report them in intensive quantity units for convenience.

`64.0 cancel("g NH"_3) xx ("1 mol NH"_3)/(17.0307 cancel("g NH"_3)) = "3.758 mol NH"_3`

And therefore, the energy change is

`color(blue)(q_(rxn)) = -"23.33 kJ"/cancel("mol NH"_3) xx 3.758 cancel("mols NH"_3) = color(blue)(-"87.7 kJ")`

What is the energy produced?