First slide

Gibb's Helmholtz equation

Question

ΔS for 4Fe_(s)+3O_2(g)→2Fe₂O_3(s) is – 550 J/mol/K.
The process is found to be spontaneous even at 298K because [ Δ H = –1650 kJ]

Moderate

Solution

For Irreversible spontaneous process , $\Delta S_{system}+\Delta S_{Surroundings}>0$
ΔS_sys = -550J
$\begin{array}{l} \Delta {S_{Surr.}} = \frac{{ - (\Delta {H_{sys}})}}{T}\\\\ \,\,\,\,\,\,\,\,\,\,\,\,\,\, = \frac{{ - ( - 1650 \times 1000)}}{{298}}\\\\ \,\,\,\,\,\,\,\,\,\,\,\,\, = 5537J \end{array}$
$\therefore \Delta S_{total}=-550+5537=4987J$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App