# What is \DeltaS for the below phase change if \DeltaH is 6010 "J"/"mol" at STD conditions?

## ${H}_{2} O \text{(s)"\rightleftharpoonsH_2O"(l)}$ (Note: please use basic chemistry terms/concepts, I just started learning this)

Jul 25, 2018

DeltaS_"fus" = "22.0 J"/{"mol"cdot"K"}

#### Explanation:

The change in entropy $\setminus \Delta S$ due to heat exchange at constant pressure, $\setminus \Delta H$, at a constant temperature $T$ in $\text{K}$, is given as

\Delta S_"trans"=\frac{\Delta H_"trans"}{T}

because a normal phase change at constant temperature and pressure is an equilibrium condition, for which

cancel(DeltaG_"trans")^(0) = DeltaH_"trans" - TDeltaS_"trans".

As per given data, and knowing that melting requires energy input (i.e. $\Delta H > 0$),

$\setminus \Delta {H}_{\text{fus"= "6010 J"/"mol}}$ & $T = {0}^{\setminus} \circ C = 273.15 \setminus K$
(freezing point of water)

\Delta S_"fus"= \frac{"6010 J/mol"}{"273.15 K"}

\ \ \ ="22.0 J"/{"mol"cdot"K"}