Open AccessDissolution of sulfuric acid tetrahydrate at low temperatures and subsequent growth of nitric acid trihydrate
Author(s) -
Iraci Laura T.,
Fortin Tara J.,
Tolbert Margaret A.
Publication year - 1998
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/98jd00281
Subject(s) - nitric acid , dissolution , sulfuric acid , tetrahydrate , crystallization , inorganic chemistry , chemistry , melting point , mineralogy , crystallography , organic chemistry , crystal structure
Crystalline sulfuric acid tetrahydrate (SAT) has been observed to change phase at temperatures below its melting point, in agreement with recent theoretical predictions of deliquescence. Dissolution of SAT was observed in 63% of experiments expected to show a phase change, leading to formation of a ternary HNO 3 /H 2 SO 4 /H 2 O solution. This solution, which still contained a portion of the original solid SAT, crystallized to form nitric acid trihydrate (NAT). NAT then continued to grow by condensation of additional nitric acid and water at temperatures several degrees above the ice frost point. This process of SAT dissolution followed by NAT crystallization and growth may offer a mechanism for the formation of type Ia polar stratospheric clouds on frozen sulfate aerosols when S NAT >15.