Verification of Clausius Clapeyron Equation

Verification of Clausius Clapeyron Equation Aim: To verify Clausius Clapeyron Equation by determining the Specific enthalpy of saturated water and saturated steam Apparatus: Fixed volume pressure cooker (3 liters), Pressure gauge (2Kg/cm 2 ), digital thermometer and a stove Principle: The specific enthalpy of saturated water (h f ) depends on its pressure in accordance with the equation, h = u + PV, by knowing the specific enthalpy of water at 1 atm and the specific enthalpy of saturated steam the specific enthalpy of evaporations can be determined as the difference of the specific enthalpy of water and specific enthalpy of saturated steam For saturated water the specific enthalpy at normal pressure of 1 atm = h f = 419kJ/kg For saturated steam the specific enthalpy = h g = 2676kJ/kg Therefore, The specific enthalpy of evaporation h gf = hg -hf =2676 – 419 = 2257kJ/kg Procedure: 1. The v olume of th e pressure c ooke r is n oted as 3 l itres . 2. The pressure coo ker fit ted wit h a pressu re gauge is f ille d with wat er up to two third of its volume. 3. The li d is c lose d and p laced on ho t pla te whi ch is s witc hed on . 4. The dig ital th ermometer is no w place d in its pos itio n and the ro om tempe ratu re is note d as 28 o C. 5. The rise in tempe ratur e with time is noti ced by the th ermometer. Wh en temperature reaches 90 o C, both the temperature and p ressure gauges are monit ored carefully. 6. Above l00 o C, the pressure in the gauge starts increasing. The temperature and pressure are recorded in table, at suitable intervals of pressure until the pressure in the cooker is released through the whistle of the cooker. The readings obtained are tabulated in the tabular column. 7. A graph is d rawn tak ing (ln P) on Y ax is and ( 1/T) along X ax is ,From th e strai ght lin e graph , the slope is calculated as Slope = h 1 gf / R R=8.3144J/mole The molecular weight of water is 18, hence h gf = h 1gf x l8 kJ/kg. Result: The linearity of the graph proves the Clausius Clapeyron equation and the specific enthalpy of evaporation hgf is found to be………………………………..J/kg

Upload
francis-anand
Category

Documents
view
220
download
0

Embed Size (px):

Transcript of Verification of Clausius Clapeyron Equation

Page 1: Verification of Clausius Clapeyron Equation

7/22/2019 Verification of Clausius Clapeyron Equation

http://slidepdf.com/reader/full/verification-of-clausius-clapeyron-equation 1/2

Verification of Clausius Clapeyron Equation

Aim: To verify Clausius Clapeyron Equation by determining the Specific enthalpy of saturated water and

saturated steam

Apparatus: Fixed volume pressure cooker (3 liters), Pressure gauge (2Kg/cm2), digital thermometer and

a stove

Principle: The specific enthalpy of saturated water (h f ) depends on its pressure in accordance with the

equation, h = u + PV, by knowing the specific enthalpy of water at 1 atm and the specific enthalpy of

saturated steam the specific enthalpy of evaporations can be determined as the difference of the specificenthalpy of water and specific enthalpy of saturated steam

For saturated water the specific enthalpy at normal pressure of 1 atm = h f = 419kJ/kg

For saturated steam the specific enthalpy = hg = 2676kJ/kg

Therefore,

The specific enthalpy of evaporation hgf = hg -hf =2676 – 419 = 2257kJ/kg

Procedure:

1. The volume of the pressure cooker is noted as 3 litres.

2. The pressure cooker fitted with a pressure gauge is filled with water up to two third of

its volume.

3. The lid is closed and placed on hot plate which is switched on.

4. The digital thermometer is now placed in its position and the room temperature is noted as 28oC.

5. The rise in temperature with time is noticed by the thermometer. When temperature reaches 90oC,

both the temperature and pressure gauges are monitored carefully.

6. Above l00oC, the pressure in the gauge starts increasing. The temperature and pressure are

recorded in table, at suitable intervals of pressure until the pressure in the cooker is releasedthrough the whistle of the cooker. The readings obtained are tabulated in the tabular column.

7. A graph is drawn taking (ln P) on Y axis and ( 1/T) along X axis ,From the straight line graph, the

slope is calculated as

Slope = h1gf / R

R=8.3144J/mole

The molecular weight of water is 18, hence hgf = h1gf x l8 kJ/kg.

Result: The linearity of the graph proves the Clausius Clapeyron equation and the specific enthalpy of

evaporation hgf is found to be………………………………..J/kg