Problem 1: A tank is divided by a rigid, thermally conducting partition into two equal parts, A and B, each 10 m3 in volume.
Part A contains saturated liquid n-butane at 20 °C, 2.07 bar;
part B contains saturated n-butane vapor, also at 20 °C, 2.07 bar. Each part is equipped with a safety alarm that will go off if pressure exceeds 40 bar.
a) How many moles of n-butane is in part A of the tank?
b) How many moles of n-butane is in part B of the tank?
c) The tank is heated slowly in such a way that the temperature in both parts rises at the same rate. As soon as the alarm goes off, the heating stops. Which alarm goes off, that of part A or part B?
d) What is the temperature when the alarm sounds?
Additional data: The volume expansivity and the isothermal compressibility of liquid n-butane are given below and may be assumed to be constant:
β = 2.54 × 10-3 K-1, κ = 3.4 × 10-4 bar-1.