Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: animez89 on April 09, 2010, 01:52:49 AM
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while mercury is very useful in barometers, mercury vapor is toxic. Given the mercury has Hvap of 56.9 kJ/mol and its normal boiling point is 356.7 C. Calculate the vapor pressure in mm Hg at room temperature, 25C
i use formula Hvap/ R x [ 1/t1 - 1/ t2]= lnP
i change 56.9kJ to 56.9 x 10^-3 J so that my Hvap
my R is 8.314 J/mol k
i change my temperature in kelvin
t1= 25+ 273= 298 and t2= 357.6 +273 = 629.7 K
i plug it in formula 56.9 x 10^-3 J/ mol / 8.314 J/mol k x ( 1/ 298k - 1/629.7k)
so i got 1.21 x 10 ^ -5
then i e^ 1.21 x 10 ^ -5
i get 1.00 which is really confusing because all my unit canceled i think maybe my formula wrong
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while mercury is very useful in barometers, mercury vapor is toxic. Given the mercury has Hvap of 56.9 kJ/mol and its normal boiling point is 356.7 C. Calculate the vapor pressure in mm Hg at room temperature, 25C
i use formula Hvap/ R x [ 1/t1 - 1/ t2]= lnP
i change 56.9kJ to 56.9 x 10^-3 J so that my Hvap
my R is 8.314 J/mol k
i change my temperature in kelvin
t1= 25+ 273= 298 and t2= 357.6 +273 = 629.7 K
i plug it in formula 56.9 x 10^-3 J/ mol / 8.314 J/mol k x ( 1/ 298k - 1/629.7k)
so i got 1.21 x 10 ^ -5
then i e^ 1.21 x 10 ^ -5
i get 1.00 which is really confusing because all my unit canceled i think maybe my formula wrong
1 kJ = 103 J, not the other way round