Single micron-size sulfuric acid droplets are levitated in vacuum in a quadrupole trap through which passes the beam from a He–Ne laser. Scattered light is monitored by a fixed detector as cavity resonances are excited in the evaporating droplet. Mie-Debye theory is used to determine particle size, which, with kinetic theory, yields vapor pressure. Over the temperature range studied, −10 to +30°C, the vapor pressure of pure sulfuric acid is lnp(Torr) = (20.70 ± 1.74) − (9360 ± 499)/T(K).
© 1986 Optical Society of America
Original Manuscript: October 28, 1985
Published: April 1, 1986
C. B. Richardson, R. L. Hightower, and A. L. Pigg, "Optical measurement of the evaporation of sulfuric acid droplets," Appl. Opt. 25, 1226-1229 (1986)