Question

What is the enthalpy of the phase transition ice to water with respect to a `20*g` mass of ice?

Answer 1

We interrogate the reaction............

Explanation:

We interrogate the phase transition............

`H_2O(s) +Deltastackrel("0" ""^@C)rarrH_2O(l)`

Since both the `"reactant"` and the `"product"` are conceived to be at the same temperatgure, we only need consider the enthalpy change of the phase transition, and we expect reasonably, that the process gives an `"endotherm"`, as we are breaking ice-ice bonds..........

And we gots a `20*g` mass of ice.......

`Delta_"phase transition"=20*gxx334*J*g^-1=+6680*J=6.68*kJ`

And this represents `6680*Jxx1/(4.184*J*"cal"^-1)=??"cal"`

And if we have a 2 molar quantity of ice, i.e. a `36*g` mass, we simply solve.......

`Delta_"phase transition"=36*gxx334*J*g^-1=+12024*J=12.0*kJ`

`~=2874*"cal"`........