Which chemical equation represents the reaction for which the enthalpy change is equal to the standard enthalpy of formation of potassium iodide, KI(s)\text{KI(s)}KI(s)?
K+(aq)+I−(aq)→KI(s)\text{K}^+\text{(aq)} + \text{I}^-\text{(aq)} \rightarrow \text{KI(s)}K+(aq)+I−(aq)→KI(s)
K(s)+12I2(g)→KI(s)\text{K(s)} + \frac{1}{2}\text{I}_2\text{(g)} \rightarrow \text{KI(s)}K(s)+21I2(g)→KI(s)
K(s)+12I2(s)→KI(s)\text{K(s)} + \frac{1}{2}\text{I}_2\text{(s)} \rightarrow \text{KI(s)}K(s)+21I2(s)→KI(s)
K(g)+12I2(l)→KI(s)\text{K(g)} + \frac{1}{2}\text{I}_2\text{(l)} \rightarrow \text{KI(s)}K(g)+21I2(l)→KI(s)
