All Problems Phase Transformations
Problem 2.215
A piece of copper of mass \(m=90 \mathrm{~g}\) at a temperature \(t_{1}\) \(=90{ }^{\circ} \mathrm{C}\) was placed in a calorimeter in which ice of mass \(50 \mathrm{~g}\) was at a temperature \(-3{ }^{\circ} \mathrm{C} .\) Find the entropy increment of the piece of copper by the moment the thermal equilibrium is reached.
2.215. \(\Delta S=m c \ln \left(T / T_{1}\right)=-10 \mathrm{~J} / \mathrm{K},\) where \(c\) is the specific heat capacity of copper, \(T=273 \mathrm{~K}\) (under these conditions only a part of the ice will melt).