2018, 3 (g) In a separate experiment, the student is given a sample of powdered Fe(s) that contains an inert
impurity. The student uses a procedure to oxidize the Fe(s) in the sample to Fe2O3(s). The student
collects the following data during the experiment.
Mass of Fe(s) with inert impurity
6.724 g
Mass of Fe2O3(s) produced
7.531 g
(g) Calculate the number of moles of Fe in the Fe2O3(s) produced.

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 :