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in the given equation 4Fe(s)+3O(2)(g) ...

in the given equation
`4Fe(s)+3O_(2)(g) to 2Fe_(2)O_(3)(s)`
the entropy change is `=-549.4 JK^(-1) mol^(-1)`at 298 K`
` (Delta_rH^(-)=-1648 xx10^(3)Jmol^(-1))`.the above reactions is

A

spontaneous

B

non-spontaneous

C

both (a) and (b)

D

none of these

Text Solution

Verified by Experts

The correct Answer is:
a

At temperature , T entropy cahange of the surroundings is
`DeltaS_(surr)=(Delta_(r)H^(Theta))/T ` ( at constant pressure) `-(-1648xx10^(3)Jmol^(-1))/(298K) `
` 5530 JK ^(-1) mol^(-1)`
`Delta_(r)S("total")=5530+(-549.4)`
`4980.6 JK^(-1)mol^(-1)`
Hence , the abouve reaction is spontaneous.
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