# Molarity (M)

Molarity of a solution is the number of moles of the solute per litre of solution (or number of millimoles per ml. of solution). Unit of molarity is **mol/litre** or **mol/dm ^{3} **For example, a molar

_{}solution of sugar means a solution containing 1 mole of sugar (i.e., 342 g or

_{}molecules of it) per litre of the solution. Solutions in term of molarity generally expressed as,

_{}= Molar solution, _{}= Molarity is two,

_{}or 0.5 M = Semimolar solution,

_{} or 0.1 M = Decimolar solution,

_{} or 0.01 M = Centimolar solution

_{} or 0.001 M = Millimolar solution

Molarity is most common way of representing the concentration of solution.

· Molarity is depend on temperature as, _{}

· When a solution is diluted (x times), its molarity also decreases (by _{} times)

Mathematically molarity can be calculated by following formulas,

(i) _{},

(ii) _{}

(iii) _{}

(iv) _{}

(v) _{}

(vi) _{}

(vii) _{}

(viii) If molarity and volume of solution are changed from _{} to _{}. Then,

_{} (Molarity equation)

(ix) In balanced chemical equation, if _{} moles of reactant one react with _{} moles of reactant two. Then,

_{}

(x) If two solutions of the same solute are mixed then molarity (M) of resulting solution.

_{}

(xi) Volume of water added to get a solution of molarity _{} from _{} of molarity _{} is

_{}