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What is molarity,molality,mole fraction,ppm and concentration of solution?
In chemistry, concentration is the abundance of a constituent divided by the total volume of a mixture.Parts per million or ppm is commonly used as aunit of concentration.

The molality of a solution b_i is defined as the amount of a constituent n_i divided by the mass of the solvent m_\mathrm{solvent} (not the mass of the solution):

b_i = \frac{n_i}{m_\mathrm{solvent}}.

The SI unit for molality is mol/kg.

The mole fraction x_i is defined as the amount of a constituent n_i divided by the total amount of all constituents in a mixture n_\mathrm{tot}:

x_i = \frac {n_i}{n_\mathrm{tot}}.

TheSI unit is mol/mol. However, the deprecated parts-per notation is often used to describe small mole fractions.

The molar concentration c_i is defined as the amount of a constituent n_i divided by the volume of the mixture V:

c_i = \frac {n_i}{V}.

The SI unit is mol/m3. However, more commonly the unit mol/L (= mol/dm3) is used.The molar concentration is also called molarity.


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