Calculate So for a each of the following reactions,

a) 2H2(g) + O2(g) ----> 2H2O(g)

Answer

We notice that the calculated value is negative. Just as we predicted on the basis of comparing the relative order/disorder of the reactants and products. In this case we concluded S was likely to be negative becaue there are more moles of gas on the reactants side compared to the product side.