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The density calculated from a volume measured using a gas pycnometer is often referred to as skeletal density, [13] [14] true density [15] [16] or helium density. [16] For non-porous solids a pycnometer can be used to measure particle density. [14] An extreme example of the gas displacement principle for volume measurement is described in U.S ...
In SI units, number density is measured in m −3, although cm −3 is often used. However, these units are not quite practical when dealing with atoms or molecules of gases, liquids or solids at room temperature and atmospheric pressure, because the resulting numbers are extremely large (on the order of 10 20).
To simplify comparisons of density across different systems of units, it is sometimes replaced by the dimensionless quantity "relative density" or "specific gravity", i.e. the ratio of the density of the material to that of a standard material, usually water. Thus a relative density less than one relative to water means that the substance ...
Methane clathrate block embedded in the sediment of hydrate ridge, off Oregon, USA. Clathrate hydrates, or gas hydrates, clathrates, or hydrates, are crystalline water-based solids physically resembling ice, in which small non-polar molecules (typically gases) or polar molecules with large hydrophobic moieties are trapped inside "cages" of hydrogen bonded, frozen water molecules.
where g is the local acceleration due to gravity, V is the volume of the sample and of water (the same for both), ρ sample is the density of the sample, ρ H 2 O is the density of water, W V represents a weight obtained in vacuum, is the mass of the sample and is the mass of an equal volume of water. The density of water and of the sample ...
A monolithic HPLC column, or monolithic column, is a column used in high-performance liquid chromatography (HPLC). The internal structure of the monolithic column is created in such a way that many channels form inside the column. The material inside the column which separates the channels can be porous and functionalized.
In a solid, constituent particles (ions, atoms, or molecules) are closely packed together. The forces between particles are so strong that the particles cannot move freely but can only vibrate. As a result, a solid has a stable, definite shape, and a definite volume. Solids can only change their shape by an outside force, as when broken or cut.
Vapour density is the density of a vapour in relation to that of hydrogen. It may be defined as mass of a certain volume of a substance divided by mass of same volume of hydrogen. vapour density = mass of n molecules of gas / mass of n molecules of hydrogen gas . vapour density = molar mass of gas / molar mass of H 2