We’re being asked to determine the Δ**G° at 25 °C for the decomposition of calcium chloride.**

**Calcium Chloride (CaCl _{2}) decomposes into solid calcium (Ca) and gaseous Chlorine (Cl_{2})**

CaCl_{2(s)} → Ca_{(s)} + Cl_{2}_{(g)}

We can use the following equation to solve for ** ΔG˚_{rxn}**:

$\overline{){\mathbf{\Delta G}}{{\mathbf{\xb0}}}_{{\mathbf{rxn}}}{\mathbf{=}}{\mathbf{\Delta G}}{{\mathbf{\xb0}}}_{\mathbf{f}\mathbf{,}\mathbf{}\mathbf{prod}}{\mathbf{-}}{\mathbf{\Delta G}}{{\mathbf{\xb0}}}_{\mathbf{f}\mathbf{,}\mathbf{}\mathbf{react}}}$

Use the table below to answer the questions that follow.

The value of G° at 25 °C for the decomposition of calcium chloride into its constituent elements,

is __________ kJ/mol.