91Ó°ÊÓ

1. Mass of the ice cube, m = 12.0 g
2. Mass of the spoonful of water, M = 5.00 g

Entropy change is a phenomenon that quantifies how disorder or randomness has changed in a thermodynamic system. We can use the formula for change in entropy in terms of heat energy. Then this heat energy can be written in terms of latent heat. Inserting respective masses, we can find the entropy change of ice and water.

Formulae:

The entropy change for an isothermal expansion, $∆S=\frac{Q}{T}$ (i)

The heat released by the body due to latent heat, Q = mL (ii)

Freezing point of water is T = 273K and latent heat of fusion of water, $L_f=333J/g$.

Change in the entropy of the ice cube for a reversible isothermal process using equations (i) and (ii) can be given as follows:

$$\begin{gathered} ∆S=\frac{m{L}_f}{T} \\ =\frac{12g×333J/g}{273K} \\ =14.637J/K \\ ≈14.6J/K \end{gathered}$$

Hence, the value of the entropy change of the ice cube is 14.6 J/K

Boiling point of water is T = 373K and latent heat of vaporization of water, $L_v=2256J/g$.

Similarly, using equations (i) and (ii), the entropy change of water is given as follows:

$$\begin{gathered} ∆S=\frac{m{L}_v}{T} \\ =\frac{5g×2256J/g}{373K} \\ =30.24J/k \\ ≈30.2J/K \end{gathered}$$

Hence, the value of entropy change of water is 30.2 J/K