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How does liquid ammonia compare with water as a solvent for organic materials?

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Difference in molecular structure between ammonia/amines and quaternary ammonium ions — ammonia Ammonia and amines have a slightly flattened trigonal pyramidal shape with a lone pair of electrons above the nitrogen. In quaternary ammonium ions, this area is occupied by a fourth substituent.

Liquid ammonia is a more effective solvent for organic materials than water. This difference is primarily attributed to their respective dielectric constants; ammonia has a lower dielectric constant (22 at −34 °C) compared to water (81 at 25 °C), which enhances its ability to dissolve organic substances.1

While water is a highly polar solvent, liquid ammonia’s lower dielectric constant makes it better suited for organic compounds, though it remains a moderately good ionizing solvent capable of supporting chemical reactions. In addition to its role as a solvent for organic materials, liquid ammonia is used extensively as a nonaqueous solvent for various inorganic substances, including alkali metals and most ammonium salts.12