## Enthalpy Predictions

$\Delta S = \frac{q_{rev}}{T}$

Kathleen Nguyen 3G
Posts: 23
Joined: Wed Sep 21, 2016 2:58 pm

### Enthalpy Predictions

When predicting the sign of dS(sys), when do you know when it should be positive or negative?
I'm doing question 2 of the Winter 2014 final and it asks us to predict the dS(sys) without doing any calculations. The equation we're predicting dS of is 2CO(g) + O2(g) --> 2CO2(g).

Banik_Housepian_2K
Posts: 39
Joined: Wed Sep 21, 2016 2:59 pm

### Re: Enthalpy Predictions

The entropy of the system decreases while the entropy of the surroundings increases. This is because we had 2 reactants compared to 1 product, and thus the entropy of the reactants is higher than that of the product.