Thermodynamics of Materials : MSE 616 PP set 05 | Department of Materials Science and Engineering Indian Institute of Technology Kanpur
Q1. Calculate the pressure required for distillation of mercury at 100°C. The vapor
pressure of liquid mercury is given as: lnP = −7611
T − 0.795lnT +17.168.
Q2. At normal boiling temperature of iron, 3330K, the rate of change of the vapor
pressure of liquid iron with temperature is 3.72x10-3 atm/K. Calculate the molar latent
heat of boiling of iron at 3330K.
Q3. The molar volumes of solid and liquid lead at the normal melting temperature of
lead (600K) are 18.92 and 19.47 cm3 respectively. Calculate the pressure that must be
applied to lead in order to increase its melting temperature by 20°C. The molar latent
heat of melting of lead at 600K is 4810 J/mol.
Q4. a. Find the triple points for the phase equilibria CaF2(α)-CaF2(β)- CaF2(v) and
CaF2(β)-CaF2(l)- CaF2(v)
b. Find the normal boiling temperature of CaF2.
Q5. (a) At 1 atm pressure and room temperature, iron exists in BCC structure
(named α-iron). Upon heating, it transforms to FCC structure (named γ iron) at
910°C. On further heating, the iron transforms back to BCC structure (named δ-iron)
at 1394°C and melts at 1538°C. Draw schematic G vs T curves, representing the
phase equilibria of iron at 1 atm.
(b) If pressure is increased to 2 atm, would the transformation temperature of
α to γ increase or decrease? Why?
Phase vapor pressure (p in atm)
CaF2(α) lnP = −54350
T − 4.525lnT + 56.57
CaF2(β) lnP = −53780
T − 4.525lnT + 56.08
CaF2(l) lnP = −50200
T − 4.525lnT + 53.96
MSE 201A
PP Set 4
Q6. Following figure shows the phase diagram for zirconia (ZrO2).
a) Indicate all stable triple points and corresponding phase equilibria
b) Draw G vs T curves for ZrO2 at P = 1atm
c) Draw G vs P curve at 2000°C. Also indicate metastable equilibria on this curve.
d) Draw G vs T curve at pressure corresponding to point a
Q7. The equation of state for hydrogen gas is given by PV = RT 1+ 6.4×10−4
( P).
Calculate the following
a. The fugacity of hydrogen at 500 atm and 298K
b. The pressure at which the fugacity is twice the pressure
c. The change in the Gibbs free energy caused by a compression of 1mole of
hydrogen at 298K from 1 to 500 atm
d. Magnitude of the contribution to the Gibbs free enrgy change in (c) from nonideality of hydrogen
α β γ L
V
