ChemNeuro
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Draw molecule at cyan panel. How to use animation1, animation2
Cis-, Trans- compounds return average
of both. Density, ratio of the mass of a substance to its volume, expressed, for example, in units of grams per cubic centimeter or pounds per cubic foot. The density of a pure substance varies little from sample to sample and is often considered a characteristic property of the substance. Most substances undergo expansion when heated and therefore have lower densities at higher temperatures. Many substances, especially gases, can be compressed into a smaller volume by increasing the pressure acting on them. For these reasons, the temperature and pressure at which the density of a substance is measured are usually specified. The density of a gas is often converted mathematically to what it would be at a standard temperature and pressure (STP). Water is unusual in that it expands, and thus decreases in density, as it is cooled below 3.98'C (its temperature of maximum density). There are several methods for estimating pure liquid specific volumes or densities.
To use these method, critical temperature ( Tc ), acentric factor, and critical pressure ( Pc ) data are needed. Our neural network method introduce correction factor from absolute molecular volume calculated from optimized structure by Molecular Orbital. |
