Respuesta :
Answer : The value of [tex]\Delta H_{vap}[/tex] is 28.97 kJ/mol
Explanation :
To calculate [tex]\Delta H_{vap}[/tex] of the reaction, we use clausius claypron equation, which is:
[tex]\ln(\frac{P_2}{P_1})=\frac{\Delta H_{vap}}{R}[\frac{1}{T_1}-\frac{1}{T_2}][/tex]
where,
[tex]P_1[/tex] = vapor pressure at temperature [tex]-21.0^oC[/tex] = 462.7 mmHg
[tex]P_2[/tex] = vapor pressure at temperature [tex]-44.0^oC[/tex] = 140.5 mmHg
[tex]\Delta H_{vap}[/tex] = Enthalpy of vaporization = ?
R = Gas constant = 8.314 J/mol K
[tex]T_1[/tex] = initial temperature = [tex]-21.0^oC=[-21.0+273]K=252K[/tex]
[tex]T_2[/tex] = final temperature = [tex]45^oC=[-41.0+273]K=232K[/tex]
Putting values in above equation, we get:
[tex]\ln(\frac{140.5mmHg}{462.7mmHg})=\frac{\Delta H_{vap}}{8.314J/mol.K}[\frac{1}{252}-\frac{1}{232}]\\\\\Delta H_{vap}=28966.6J/mol=28.97kJ/mol[/tex]
Therefore, the value of [tex]\Delta H_{vap}[/tex] is 28.97 kJ/mol
