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Phase Transformations

Problem 2.189

An amount of water of mass \(m=1.00 \mathrm{~kg}\), boiling at standard atmospheric pressure, turns completely into saturated vapour. Assuming the saturated vapour to be an ideal gas find the increment of entropy and internal energy of the system.

Reveal Answer
 2.189. ΔS=mq/T=6.0 kJ/K;ΔU=m(qRT/M)=2.1MJ where T=373 K\begin{aligned} &\text { 2.189. } \Delta S=m q / T=6.0 \mathrm{~kJ} / \mathrm{K} ; \quad \Delta U=m(q-R T / M)=2.1 \mathrm{MJ}\\ &\text { where } T=373 \mathrm{~K} \end{aligned}