%0 Journal Article
%T Reinvestigation of the Henry''s law constant for hydrogen peroxide with temperature and acidity variation<br>Reinvestigation of the Henry’s law constant for hydrogen peroxide with temperature and acidity variation
%A Daoming Huang
%A Zhongming Chen
%A <br>Daoming Huang
%A Zhongming Chen
%J 环境科学学报(英文版)
%D 2010
%I 
%X Hydrogen peroxide is not only an important oxidant in itself; it also serves as both sink and temporary reservoir for other important oxidants including HOx (OH and HO_2) radicals and O_3 in the atmosphere. Its partitioning between gas and aqueous phases in the atmosphere, usually described by its Henry's law constant (K_H), significantly influences its role in atmospheric processes. Large discrepancies between the K_H values reported in previous work, however, have created uncertainty for atmospheric modelers. Based on our newly developed online instrumentation, we have re-determined the temperature and acidity dependence of K_H for hydrogen peroxide at an air pressure of (0.960±0.013) atm (1 atm = 1.01325×10~5 Pa). The results indicated that the temperature dependence of KH for hydrogen peroxide fits to the Van't Hoff equation form, expressed as lnK_H= a/T - b, and a = -△H/R, where K_H is in M/atm (M is mol/L), T is in degrees Kelvin, R is the ideal gas constant, and △H is the standard heat of solution. For acidity dependence, results demonstrated that the K_H value of hydrogen peroxide appeared to have no obvious dependence on decreasing pH level (from pH 7 to pH 1). Combining the dependence of both temperature and acidity, the obtained a and b were 7024±138 and 11.97±0.48, respectively, △H was (58.40±1.15) kJ/(K·mol), and the uncertainties represent σ. Our determined K_H values for hydrogen peroxide will therefore be of great use in atmospheric models.
%K hydrogen peroxide
%K Henry's law constant
%K atmosphere
%K acidity<br>hydrogen
%K peroxide
%K Henry’s
%K law
%K constant
%K atmosphere
%K acidity
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=3FF3ABA7486768130C3FF830376F43B398E0C97F0FF2DD53&cid=A7CA601309F5FED03C078BCE383971DC&jid=6CB1530875F53489BF1E81BD87B7F5E6&aid=6D5BA8448EC5BD48BCB2481D047CACDC&yid=140ECF96957D60B2&vid=BC12EA701C895178&iid=E158A972A605785F&sid=18F040DBCB74FFF9&eid=F6467E7C54ED952D&journal_id=1001-0742&journal_name=Journalofenvironmentalsciences(China)&referenced_num=0&reference_num=24