The chemical reaction that causes aluminum to corrode in air is given by 4Al+3O2

Question

The chemical reaction that causes aluminum to corrode in air is given by

4Al+3O2 --> 2Al2O3

in which;

deltaHreact = -3352kJ

deltaSreact = -625.1 J/K

Part A= (already answered)

deltaGreact = -3166kJ

Part B=

Express your answer to two decimal places and include the appropriate units.

The chemical reaction that causes aluminum to corrode in air is given by 4Al+3O2 --> 2Al2O3 in which; deltaHreact = -3352kJ deltaSreact = -625.1 J/K Part A= (already answered) What is the standard Gibbs free energy for this reaction? Assume the commonly used standard reference temperature of 298 K. Express your answer as an integer and include the appropriate units. deltaGreact = -3166kJ What is the Gibbs free energy for this reaction at 5975K ? Assume that delta H and delta S do not change with temperature Express your answer to two decimal places and include the appropriate units.

Explanation / Answer

Gibbs free energy or (delta G) = delta H - (Kelvins * delta S) (Abbreviated -->) G = H - (K*S)   SO, you plug in the given values except K is 5975 K instead of 298 K(chem lab room temp.) All you have to know is to multiply kelvins and the delta S(in kJ) FIRST then subtract delta H as is in kJ.         NOTE that everything must be in kJ. You could put everything in J but the final answer is asking for kJ (so don't waste any solving timeconvert to kJ). ALSO NOTE that delta S is originally J/K(elvin) and when you multiply K * J/K kelvins cancel out and that product becomes Jules. So now you'll have delta H(kJ) minus that product in (J) and you cannot add or subtract numbers with unlike units. FINAL NOTE converting J/K to kJ/K is the same as converting J to kJ (move left 3 decimal places for J to kJ)<--- (Jules to KILOJules) Kilo is a thousand times larger value so if your talking about one type of number the number itself is a thousand times smaller, 1kilo is 1000(anything). (that 1 kiloJule is a thousand times smaller NUMBER but is the SAME VALUE as one Jule)

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.