Question

What is the entropy change associated with the chemical reaction that occurs when iron oxide is converted to its metal form?
Fe2O3(s) + 3CO(g) ? 2Fe(s) + 3CO2(g)

A. Positive
B. Zero
C. Cannot be determined
D. Negative

Answer 1

do you know what entropy is a measurement of?

Answer 2

randomness

Answer 3

I feel that it cannot be determined because both the reactants and the products have one solid and one gas, but I'm not sure.

Answer 4

yes, but HOW MUCH of each solid and gas?

Answer 5

the reactants have 1 mole of solid and 3 moles of gas, while the products have the same 3 moles of gas, and 2 moles of solid

Answer 6

the change in entropy might not be large, but its sign should be determinable

Answer 7

So the entropy decreases?

Answer 8

other way

Answer 9

in general, 2 moles of a solid are MORE disordered than 1 mole of a solid

Answer 10

oh ok. I thought of the ratio of the gas to the solid

Answer 11

you have to look at the whole reaction to really see the entropy difference of the overall reaction

Answer 12

Ok. Thanks!