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 what is molality,normality and molari...
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Molarity
Molarity (M) is defined as the number of moles of solute per liter of solution. molarity = moles of solute / liters of solution
Molality
Molality (m) is defined as the number of moles of solute per kilogram of solvent. molality = moles of solute / kilograms of solvent
Although their spellings are similar, molarity and molality cannot be interchanged. Compare the molar and molal volumes of 1 mol of solute dissolved in CCl_{4} (d = 1.59 g / mL)
By definition, a 1 M solution would contain 1 mol of solute in exactly 1.00 L of CCl_{4} , and a 1 m solution would contain 1 mol of solute in 629 mL of CCl_{4} . 1 kg of CCl_{4} x (1000 g / 1 kg) x (mL / 1.59 g) = 629 mL CCl_{4}
Normality
Normality (N) is another ratio that relates the amount of solute to the total volume of solution. It is defined as the number of equivalents per liter of solution:
normality = number of equivalents / 1 L of solution
There is a very simple relationship between normality and molarity:
N = n Ã— M (where n is an integer)
For an acid solution, n is the number of H^{+} provided by a formula unit of acid.
example: A 3 M H_{2}SO_{4} solution is the same as a 6 N H_{2}SO_{4} solution.
For a basic solution, n is the number of OH^{} provided by a formula unit of base.
example: A 1 M Ca(OH)_{2} solution is the same as a 2N Ca(OH)_{2}^{ }solution.
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