# Question d857d

Jun 5, 2017

We need the latent heat of fusion of ice..........and get $16.7 \cdot k J$.

#### Explanation:

This site quotes the latent heat of fusion of water as $333.55 \cdot J \cdot {g}^{-} 1$, and this the measures the enthalpy change for the transition:

${H}_{2} O \left(s\right) + \Delta \rightarrow {H}_{2} O \left(l\right)$.

These data should have been supplied with your question, as, clearly, you (or I!) could not be expected to remember it. Since both the ice and the water are at $0$ ""^@C# we only need to assess the enthalpy of the phase change.........and thus......

$50 \cdot g \times 333.55 \cdot J \cdot {g}^{-} 1 \times {10}^{-} 3 \cdot k J \cdot {J}^{-} 1 = 16.7 \cdot k J$

How would the answer change if we were asked to assess the enthalpy for the transition liquid water to solid ice?