What is the enthalpy of formation? the overall enthalpy change that occurs when one mole of substance is formed from its elements
the overall enthalpy change that occurs when a substance is formed from one molecule of its elements
the enthalpy needed to start a reaction and cause elements to form one mole of a new substance

i believe the answer is a.

answer: the value of enthalpy change will be -152.80 kj.

solution:

pressure = 1atm , temperature = = 298 k

given that pressure and temperature are same in both gases , the number of moles of both gases can be determined by the ideal gas equation.

according to reaction 3 moles no are reacting with 1 mol of ,then 0.49 mol of no will react with moles of ozone that is 0.16 moles of ozone. since, no is limiting reagent and is an excessive reagent.

enthalpy change for the reaction between the given volumes of the gases is :