Practice Questions on Phase diagrams and Phase Rule | Physical Chemistry PDF Download

Q.1. Values of vapour at temperature and pressure exceeding those at saturation is
(a) Superheated vapour
(b) Sub-cooled vapour
(c) Below critical point vapour
(d) None of the mentioned

Correct Answer is Option (a)
Values of vapour at temperature and pressure exceeding those at saturation is Superheated vapour. 

Q.2. Change in phase from solid to vapour
(a) Melting
(b) Boiling
(c) Evaporation
(d) Sublimation

Correct Answer is Option (d)
Change in phase from solid to vapour is Sublimation. 

Q.3. Saturated liquid or saturated vapour can be found
(a) Along the liquid and vapour equilibrium curve
(b) Along the liquid and solid equilibrium curve
(c) Along the solid and vapour equilibrium curve
(d) None of the mentioned

Correct Answer is Option (a)
Saturated liquid or saturated vapour can be found along the liquid and vapour equilibrium curve. 

Q.4. The temperature at which a liquid will begin to boil at the standard atmospheric pressure is
(a) Normal boiling point
(b) Normal melting point
(c) Normal freezing point
(d) None of the mentioned

Correct Answer is Option (a)
The temperature at which a liquid will begin to boil at the standard atmospheric pressure is Normal boiling point. 

Q.5. Boiling occurs at ______ temperature and ______ pressure, the process appears as a point in ______ diagram.
(a) Constant, constant, P-T
(b) Variable, constant, P-T
(c) Constant, variable, V-T
(d) Variable, variable, V-T

Correct Answer is Option (a)
Boiling occurs at constant temperature and constant pressure, the process appears as a point in P-T diagram. 

Q.6. The pressure along the melting curve is
(a) Sublimation pressure
(b) Saturation pressure
(c) Condensation pressure
(d) None of the mentioned

Correct Answer is Option (a)
The pressure along the melting curve is Sublimation pressure. 

Q.7. The liquid between the melting curve and the vapour pressure curve is Sub-cooled liquid. 
The above given statement is
(a) False
(b) True
(c) Cannot be predicted for any material
(d) None of the mentioned

Correct Answer is Option (b)
The liquid between the melting curve and the vapour pressure curve is Subcooled liquid. 

Q.8. The temperature at which the solid melts at 1 atm is called
(a) Normal boiling point
(b) Normal melting point
(c) Normal freezing point
(d) None of the mentioned

Correct Answer is Option (b)
The temperature at which the solid melts at 1 atm is called Normal melting point. 

Q.9. The change of phase from liquid to solid is
(a) Freezing
(b) Evaporation
(c) Sublimation
(d) None of the mentioned

Correct Answer is Option (a)
The change of phase from liquid to vapour is Freezing. 

Q.10. The change of phase from liquid to vapour is
(a) Condensation
(b) Evaporation
(c) Sublimation
(d) None of the mentioned

Correct Answer is Option (b)
The change of phase from liquid to vapour is Evaporation.