Answer to Question #301409 in General Chemistry for jennjenn

Question

The standard enthalpy changes for the formation of aluminium oxide and iron (III) oxide are:

2 Al(s) + 3/2 O2 (g) Al203(s) ∆H= -1676 kJ/mol

2 Fe (s) + 3/2 O2 (g) Fe2O3 (s) ∆H= -824 kJ/mol

Answer 1

Enthalpy of formation is Enthalpy change when 1 mol . Of compound is formed by most stable physical state .

Enthalpy change and reaction of formation of Aluminium oxide is

Al + 3/2 O₂ = Al₂O₃ H = - 1676 kj / mol .

Enthalpy change and formation of iron ( III ) Oxide .

2 Fe + 3/2 O₃ = Fe₂O₃ . H = - 824 kj / mol .