The standard heat of the reaction is H r = 904:7 kJ. (a) Briefly explain what that

The standard heat of the reaction

is ΔH_r = 904:7 kJ.

(a) Briefly explain what that means. Your explanation may take the form “When ______ (specify quantities of reactant species and their physical states) react to form ______ (quantities of product species and their physical state), the change in enthalpy is ______.”

(b) Is the reaction exothermic or endothermic at 25°C? Would you have to heat or cool the reactor to keep the temperature constant? What would the temperature do if the reactor ran adiabatically?

What can you infer about the energy required to break the molecular bonds of the reactants and that released when the product bonds form?

(c) What is ΔH_r for

(d) What is ΔH_r for

(e) Estimate the enthalpy change associated with the consumption of 340 g NH₃/s if the reactants and products are all at 25°C. What have you assumed about the reactor pressure? (You don’t have to assume that it equals 1 atm.)

 (f) The values of ΔH_r given in this problem apply to water vapor at 25°C and 1 atm, and yet the normal boiling point of water is 100°C. Can water exist as a vapor at 25°C and a total pressure of 1 atm? Explain your answer.

Transcribed Image Text:

4NH3(g)+ 502(g) → 4NO(g) + 6H2O(g)