The dissolution process is represented by the following equation:

$CaC{l}_2(s)longrightarrowC{a}^{2+}(aq)+2C{l}^{-}(aq)$

The value for $H$ is $81\mathrm{.}8kJ$ for the reaction as written. $($No sign has been included, as you are asked for that in Part $1)$