When water is added to quicklime, heat is evolved and after sometime you get a turbid solution of

During the formation of slaked lime, heat energy is released.

$\text{CaO}+{\text{H}}_{\text{2}}\text{O}\to \text{Ca}{\left(\text{OH}\right)}_{\text{2}}+\text{heat\hspace{0.17em}energy}$

If $\text{Ca}{\left(\text{OH}\right)}_2$ reacts with ${\text{CO}}_2$present in the atmosphere to form turbid solution ${\text{CaCO}}_{\text{3}}$. The chemical reaction is

$\text{Ca}{\left(\text{OH}\right)}_2+{\text{\hspace{0.17em}\hspace{0.17em}CO}}_2\to {\text{\hspace{0.17em}\hspace{0.17em}CaCO}}_{\text{3}}\left(s\right)+{\text{\hspace{0.17em}\hspace{0.17em}H}}_{\text{2}}\text{O\hspace{0.17em}}\left(l\right)$