Calculate the entropy change (`DeltaS`) for the following reaction at `25^@C`.
`SO_2(g) + 1/2O_2(g) to SO_3(g)`
The absolute entropies at `25^@C` and 1 atm pressure for `SO_2(g), O_2(g) and SO_3(g)` are 248.5, 205.0 and 256.2 J K^(-1) mol^(-1)` respectively.

Explanation

To calculate the entropy change (ΔS) for the reaction \( SO_2(g) + \frac{1}{2} O_2(g) \rightarrow SO_3(g) \) at \( 25^\circ C \), we will use the formula:

\[ \Delta S = \sum S^\circ_{\text{products}} - \sum S^\circ_{\text{reactants}} \]

### Step-by-Step Solution:

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