1. The problem statement, all variables and given/known data The metal Eborium (Eb) has three solid phases: a, b, c. At a pressure of 0.45 atm, the a and b phase coexist at 70 K (temperature). The molar volume of Eb(a) is 1.23 liter/mole and that of Eb(b) is 1.47 liter/mole. The heats of transformation are as follows: Eb(a) ---> Eb(c) delta H (a --> c) = 375.8 J/mole Eb(b) ---> Eb(c) delta H (b --> c)= 24.3 J/mole At a pressure of 0.59 atm, three phases may be present. Determine the temperature at which the system must be brought to insure that three phases are present (Assume this is close to 77 K (temperature)). 2. Relevant equations Clausius-Clapeyron: 1)dp/dT= deltaH/(T deltaV) or 2)ln(p2/p1)= - (deltaH/R)(1/T2 - 1/T1) 3. The attempt at a solution I integrated eqn 1) on both sides and got p= (deltaH/deltaV) lnT2/T1 and got 2 equations after that by plugging eveything in : p= (375.8/1.23) ln T2/77 and p= (24.3/1.47) ln T2/77. When I equate these two equations I get T2=77 K which doesn't seem right. What am I doing wrong? What's confusing me is that the question says "three solid phases a, b and c" so am I using the right equations?