Question

4Al + 3O2->2Al2O3(triangle)H= -1669kj/mol
2Fe + O2 ->2FeO (triangle)H= -822 kj/mol
Determine enthalpy change?

Answer 1

Enthalpy change of what? You have the delta H values for each equation written. Perhaps you need to clarify your question if this is not what you want.

Answer 2

Here is the complete question.
Determine the enthalpy change for the single replacement reaction between aluminum oxide and iron that produces aluminum and iron (II) oxide, given that the standard enthalpy of formation for aluminum oxide is -1669 KJ/mol and for iron (II) oxide is -822 KJ/mol.

Answer 3

3Fe+Al2O3>> 3FeO + 2Al

deltaH= 3*Hf(FeO)-Hf(Al203)
= 3*(-822kJ/mol)-(-1669 kJ/mol)

you do the math.

Answer 4

huh? I'm not very good in chem but so far for the balanced equation i have:
Al2O3 + 3Fe -> 2Al + 3FeO

and then i put:
4Al +3O2 ->2Al2O3 deltaH= -1669 KJ/mol
2Fe + O2 -> 2FeO deltaH= -822 KJ/mol

i just don't know how to do the thermodynamics thingy, when you cross them out?

Answer 5

Edna. I gave you the answer from Hess' Law.

Here is what I suggest: It seems to me that something really simple has you flustered and you are not seeing the process of solution. Find a classmate who can sit down with you and go through some of these. Quickly before you are overwhelmed.

Answer 6

:) Thanks, alright I will.

Answer 7

847