Law of definite proportions
In chemistry, the law of definite proportions, sometimes called Proust's law, or law of constant composition states that a given chemical compound always contains its component elements in fixed ratio
Molecular mass
The molecular mass (m) is the mass of a given molecule: it is measured in daltons (Da or u). Different molecules of the same compound may have different molecular masses because they contain different
Relative atomic mass
Relative atomic mass (symbol: Ar; sometimes abbreviated RAM or r.a.m.), also known by the deprecated synonym atomic weight, is a dimensionless physical quantity defined as the ratio of the average mas
Atomic theory
Atomic theory is the scientific theory that matter is composed of particles called atoms. Atomic theory traces its origins to an ancient philosophical tradition known as atomism. According to this ide
Avogadro's law
Avogadro's law (sometimes referred to as Avogadro's hypothesis or Avogadro's principle) or Avogadro-Ampère's hypothesis is an experimental gas law relating the volume of a gas to the amount of substan
Loschmidt constant
The Loschmidt constant or Loschmidt's number (symbol: n0) is the number of particles (atoms or molecules) of an ideal gas in a given volume (the number density), and usually quoted at standard tempera
Osmotic pressure
Osmotic pressure is the minimum pressure which needs to be applied to a solution to prevent the inward flow of its pure solvent across a semipermeable membrane.It is also defined as the measure of the
Boiling-point elevation
Boiling-point elevation describes the phenomenon that the boiling point of a liquid (a solvent) will be higher when another compound is added, meaning that a solution has a higher boiling point than a
Amount of substance
In chemistry, the amount of substance n in a given sample of matter is defined as the quantity or number of discrete atomic-scale particles in it divided by the Avogadro constant NA. The particles or
Osmometer
An osmometer is a device for measuring the osmotic strength of a solution, colloid, or compound. There are several different techniques employed in osmometry:
* Vapor pressure osmometers determine th
Molar concentration
Molar concentration (also called molarity, amount concentration or substance concentration) is a measure of the concentration of a chemical species, in particular of a solute in a solution, in terms o
Osmotic concentration
Osmotic concentration, formerly known as osmolarity, is the measure of solute concentration, defined as the number of osmoles (Osm) of solute per litre (L) of solution (osmol/L or Osm/L). The osmolari
Gas constant
The molar gas constant (also known as the gas constant, universal gas constant, or ideal gas constant) is denoted by the symbol R or R. It is the molar equivalent to the Boltzmann constant, expressed
Standard atomic weight
The standard atomic weight of a chemical element (symbol Ar°(E) for element "E") is the weighted arithmetic mean of the relative isotopic masses of all isotopes of that element weighted by each isotop
Freezing-point depression
Freezing-point depression is a drop in the minimum temperature at which a substance freezes, caused when a smaller amount of another, non-volatile substance is added. Examples include adding salt into
Avogadro constant
The Avogadro constant, commonly denoted NA or L, is the proportionality factor that relates the number of constituent particles (usually molecules, atoms or ions) in a sample with the amount of substa
Amagat
An amagat is a practical unit of volumetric number density. Although it can be applied to any substance at any conditions, it is defined as the number of ideal gas molecules per unit volume at 1 atm (
Molar mass constant
The molar mass constant, usually denoted by Mu, is a physical constant defined as one twelfth of the molar mass of carbon-12: Mu = M(12C)/12. The molar mass of any element or compound is its relative
Equivalent weight
In chemistry, equivalent weight (also known as gram equivalent) is the mass of one equivalent, that is the mass of a given substance which will combine with or displace a fixed quantity of another sub
Colligative properties
In chemistry, colligative properties are those properties of solutions that depend on the ratio of the number of solute particles to the number of solvent particles in a solution, and not on the natur