Formation of nitric acid hydrates - a chemical equilibrium approach

Journal Article · Wed Aug 01 04:00:00 EDT 1990 · Geophysical Research Letters (American Geophysical Union); (USA)

DOI:https://doi.org/10.1029/GL017i009p01291· OSTI ID:6218447

Smith, R H ^[1]

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1. California Institute of Technology, Pasadena (USA)

Published data are used to calculate equilibrium constants for the reactions: HNO{sub 3}.3H{sub 2}O(s) {rightleftharpoons} HNO{sub 3}(g) + 3H{sub 2}O(g) and HNO{sub 3}.H{sub 2}O(s) {rightleftharpoons} HNO{sub 3}(g) + H{sub 2}O(g) over the temperature range 190 to 205 K. Standard enthalpies of formation and standard entropies are calculated for the tri- and mono-hydrates. These are shown to be in reasonable agreement with earlier calorimetric measurements. The formation of nitric acid trihydrate in the polar stratosphere is discussed in terms of these equilibrium constants.

• OSTI ID: 6218447
• Journal Information: Geophysical Research Letters (American Geophysical Union); (USA), Journal Name: Geophysical Research Letters (American Geophysical Union); (USA) Vol. 17:9; ISSN GPRLA; ISSN 0094-8276
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540110*
ATMOSPHERIC CHEMISTRY
CALORIMETRY
CHEMICAL REACTIONS
CHEMISTRY
CLOUDS
DEHYDRATION
EARTH ATMOSPHERE
ENTHALPY
ENTROPY
EQUILIBRIUM
HYDRATES
HYDRATION
HYDROGEN COMPOUNDS
INORGANIC ACIDS
NITRIC ACID
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
POLAR REGIONS
SOLVATION
STRATOSPHERE
THERMODYNAMIC PROPERTIES