Subject: Preparatory problems

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Hello Russia. Nice problems, and a lot of work. Congratulations. Here is my question: why don't we all finally agree on standard pressure 1 bar? Poor IUPAC is trying hard for almost 25 years now to convince us about 1 bar. I think at least we as teachers should help. Otherwise there is always going to be some mixup. At theoretical problem no. 6 the standard pressure is 1 atm, and in problem no. 7 obviously 1 bar, since all the pressure units are in bar. So, my modest proposition would be: let's use 1 bar.

Best regards
     Andrej Godec
     Slovenia

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Dear Andrej.
    Thank you for the compliments. We did our best to provide all the young chemists and their teachers with challenging chemistry.
    Concerning you question I must say that, of course, we support IUPAC recommendations and use 1 bar wherever it is necessary. However, we try to be flexible and adopt even old standards. Actually, the choice of standard state affects only the figures not the idea of the calculation. In addition, many old thermodynamic tables were composed with respect to standard pressure 1 atm. Of course, during the competition we will use only 1 bar, but in the preparatory problems we would like to show the students that there exist other standard values, not only 1 bar. We believe that it will not cause any confusion.
    Best wishes to you and your students.
Vadim Eremin,
    Professor of physical chemistry, MSU