Studies of single aerosol particles containing malonic acid, glutaric acid, and their mixtures with sodium chloride. II. Liquid-state vapor pressures of the acids.
The vapor pressures of two dicarboxylic acids, malonic acid and glutaric acid, are determined by the measurement of the evaporation rate of the dicarboxylic acids from single levitated particles. Two laboratory methods were used to isolate single particles, an electrodynamic balance and optical tweezers (glutaric acid only). The declining sizes of individual aerosol particles over time were followed using elastic Mie scattering or cavity enhanced Raman scattering. Experiments were conducted over the temperature range of 280-304 K and a range of relative humidities. The subcooled liquid vapor pressures of malonic and glutaric acid at 298.15 K were found to be 6.7(-1.2)(+2.6) x 10(-4) and 11.2(-4.7)(+9.6) x 10(-4) Pa, respectively, and the standard enthalpies of vaporization were respectively 141.9 ± 19.9 and 100.8 ± 23.9 kJ mol(-1). The vapor pressures of both glutaric acid and malonic acid in single particles composed of mixed inorganic/organic composition were found to be independent of salt concentration within the uncertainty of the measurements. Results are compared with previous laboratory determinations and theoretical predictions.
Pope
Francis D
FD
Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK. fdp21@cam.ac.uk
Tong
Hai-Jie
HJ
Dennis-Smither
Ben J
BJ
Griffiths
Paul T
PT
Clegg
Simon L
SL
Reid
Jonathan P
JP
Cox
R Anthony
RA
D000336:Aerosols / Q000737:chemistry; D005977:Glutarates / Q000737:chemistry*; D008314:Malonates / Q000737:chemistry*; D010316:Particle Size; D012965:Sodium Chloride / Q000737:chemistry*; D013059:Spectrum Analysis, Raman; D055548:Vapor Pressure
D000336:Aerosols; D005977:Glutarates; D008314:Malonates; D012965:Sodium Chloride; C030290:malonic acid; C035736:glutaric acid