What am I doing wrong?
Estimate the normal boiling point of liquid mercury
Hg(l) <--> Hg(g)
Hf 0.0 61.4
S 75.9 174.97
DH = 61.4 kJ
DS = .09907
T = DH/DS
= 619.76 - 273
= 346. 76 degrees celsius
1 answer
You may not be doing anything wrong. This is an estimate but that's all this equation will do for you; i.e., estimate. The values you look up in a table are the so-called standard values @ 25o C and we make the assumption that these values don't change with temperature. Actually they do change but it allows us to make estimations. I looked up the values to check your numbers and I found the same numbers except for very minor differences. For example, I found 61.38 instead of 61.4. I've not had enough experience with these things to know if 10o is usual or not. I do know that using this procedure to estimate the boiling point of water we get 97o C which is within three degrees of the correct answer and we are using numbers 75 degrees away. Mercury is another 330 degrees away so it may not be that bad an estimate. If I find something else I will post it.
1 answer