TH 202 EBULLIOMETRIC DETERMINATION OF

VAPOUR PRESSURE

• Sandip Mandal(09302021)

• Utsab Mukherjee(123020004)

OBJECTIVES

• To determine the saturation temperature of a liquid at a given pressure.

• To determine Antoine constants (A,B)

• To determine latent heat of vaporization.

THEORY • Boiling point temperature is the temperature

at which vapor pressure of the liquid becomes equal to the ambient pressure and liquid turns into vapor.

• The dependence of vapor pressure of the liquid at a given temperature is given by Clausius-Clapeyron equation

Where ΔH is enthalpy of vaporization

It can be modified to give Antoine equation lnP=A –B/(T+C) Where B=

Experimental set up

Observations

Correction factor=19 mm Hg

Results

Slope=-B=-3780 k^-1, intercept=A=17.385

B=

R=8.314 J/mol.K , ΔZv=1 ΔH=31.427 KJ/mol

Safety measurements • Don’t increase the rheostat voltage

excessively. It may lead to very fast generation vapor causing poor condensation. Finally vapor can deposit as liquid in the manometer.

• Don’t go below vacuum pressure of 300 mm Hg. It may lead to the abovementioned problem.

THANK YOU