• DOI:10.1039/B417366J
• Corpus ID: 19012439

Direct observation of completely processed calcium carbonate dust particles.

@article{Laskin2005DirectOO,
  title={Direct observation of completely processed calcium carbonate dust particles.},
  author={Alexander Laskin and Martin J. Iedema and Aviad Ichkovich and Ellen R. Graber and Ilya Taraniuk and Yinon Rudich},
  journal={Faraday discussions},
  year={2005},
  volume={130},
  pages={
          453-68; discussion 491-517, 519-24
        }
}

• A. Laskin, M. J. Iedema, +3 authors Y. Rudich
• Published 2 August 2005
• Environmental Science
• Faraday discussions

This study presents, for the first time, field evidence of complete, irreversible processing of solid calcium carbonate (calcite)-containing particles and quantitative formation of liquid calcium nitrate particles apparently as a result of heterogeneous reaction of calcium carbonate-containing mineral dust particles with gaseous nitric acid. Formation of nitrates from individual calcite and sea salt particles was followed as a function of time in aerosol samples collected at Shoresh, Israel. Morphology and compositional changes of individual particles were observed using conventional scanning electron microscopy with energy dispersive analysis of X-rays (SEM/EDX) and computer controlled SEM/EDX. Environmental scanning electron microscopy (ESEM) was utilized to determine and demonstrate the hygroscopic behavior of calcium nitrate particles found in some of the samples. Calcium nitrate particles are exceptionally hygroscopic and deliquesce even at very low relative humidity (RH) of 9-11% which is lower than typical atmospheric environments. Transformation of non-hygroscopic dry mineral dust particles into hygroscopic wet aerosol may have substantial impacts on light scattering properties, the ability to modify clouds and heterogeneous chemistry.