Identify the product ' Z ' in the following series of reactions.

Which of the following has highest solubility in water?

Calculate the standard enthalpy change for reaction,

$$ \begin{aligned} & \mathrm{C}_2 \mathrm{H}_5 \mathrm{OH}_{(l)}+3 \mathrm{O}_{2(\mathrm{~g})} \longrightarrow 2 \mathrm{CO}_{2(\mathrm{~g})}+3 \mathrm{H}_2 \mathrm{O}_{(l)} \\ & \text { if } \Delta_{\mathrm{f}} \mathrm{H}^{\circ}\left(\mathrm{C}_2 \mathrm{H}_5 \mathrm{OH}\right)=-280 \mathrm{~kJ} \mathrm{~mol}^{-1} \\ & \Delta_{\mathrm{f}} \mathrm{H}^{\circ}\left(\mathrm{CO}_2\right)=-390 \mathrm{~kJ} \mathrm{~mol}^{-1} \\ & \Delta_{\mathrm{f}} \mathrm{H}^{\circ}\left(\mathrm{H}_2 \mathrm{O}\right)=-285 \mathrm{~kJ} \mathrm{~mol}^{-1} \end{aligned} $$

Determine the expected value of $\Delta T_f$ for $1 \mathrm{~m} \mathrm{CaCl}_2$ solution if 1 m urea solution has $\Delta \mathrm{T}_{\mathrm{f}}$ value ' $x$ ' K .