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Question 6.1: A mixture of ice and water is heated up in such a way that t...

A mixture of ice and water is heated up in such a way that the ice melts. The ice melts at a rate r and the molar latent heat of ice melting is \ell_{s\ell}.

a) Determine the thermal power P_Q transferred to the ice.

b) Determine the entropy rate of change \dot{S} .

Numerical Application:

Ω = 2.0 · 10^{−2} mol s^{−1}, \ell_{s\ell} = 6.0 · 10^3 J mol^{−1}.

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a) The thermal power transferred to the ice is,

P_Q = \ell_{s \ell}Ω = 120 W.

b) The entropy rate of change is,

\dot{S} = \frac{P_Q}{T_m} = \frac{\ell_{s \ell}Ω}{T_m} = 0.44 W K^{−1} .

where T_m = 273 K is the ice melting temperature.

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