How to Calculate the Molar Heat of Vaporization of Dichloromethane?

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SUMMARY

The discussion focuses on calculating the molar heat of vaporization of dichloromethane (CH2Cl2) using its vapor pressure at 0 degrees Celsius (134 mmHg) and its normal boiling point (40.0 degrees Celsius). The equation ln(P2/134) = (ΔH_vap/8.314)(1/(0+273) - 1/(40+273)) is utilized to derive the heat of vaporization, with ΔH_vap being the unknown variable. The participant successfully resolves the problem with the provided information, confirming the boiling point as the temperature where vapor pressure equals environmental pressure.

PREREQUISITES
  • Understanding of vapor pressure and boiling point concepts
  • Familiarity with the Clausius-Clapeyron equation
  • Basic knowledge of thermodynamics and phase transitions
  • Proficiency in using natural logarithms in calculations
NEXT STEPS
  • Study the Clausius-Clapeyron equation in detail
  • Learn about phase transitions and their thermodynamic implications
  • Explore the properties of dichloromethane and its applications
  • Investigate the relationship between vapor pressure and temperature
USEFUL FOR

Chemistry students, thermodynamics enthusiasts, and professionals involved in chemical engineering or physical chemistry will benefit from this discussion.

Kudo Shinichi
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HELP!A question on vapour pressure

Homework Statement


The vapor pressure of dichloromethane, CH2Cl2, at 0 degree Celsius is 134 mmHg. The normal boiling point of dichloromethane is 40.0 degree Celsius. Calculate its molar heat of vaporization.


Homework Equations





The Attempt at a Solution



ln(P_2/134)=(Change of H_vapour/8.314)(1/(0+273)-1/(40+273))
I still have two unknown variables...I should find change H_vapour for this question, but I don't know how to figure out P_2

Thank you for helping me.
 
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What does boliling mean?
 


Borek said:
What does boiling mean?

Boiling (also called ebullition), a type of phase transition, is the rapid vaporization of a liquid, which typically occurs when a liquid is heated to its boiling point, the temperature at which the vapor pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding environmental pressure
Source: wikipedia
 


Answer to your problem is directly addressed in the quote.
 


Thanks. I have got the answer.
 

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