Reactions using reactants in solution
In order to carry out reactions using the reactants in solution, it is critical to have a measure of the amount in moles of substance present in a certain volume of solution.
Concentration indicates the quantity of solute (substance dissolved) in a volume of solution.
Standard solutions have an exactly known concentration and can be prepared by
Only a limited number of substances are primary standards. To be used as a primary standard a substance must be
Two examples of primary standards are Na2CO3·10H2O and H2C2O4·2H2O (oxalic acid).
Concentration indicates the quantity of solute (substance dissolved) in a volume of solution.
 volumetric flask |
- weighing exactly the desired amount of a solid known as a primary standard
- transferring the solid quantitatively (A procedure that involves exact work.) to a volumetric flask
- diluting to the line to give an accurately measured volume of solution.
Only a limited number of substances are primary standards. To be used as a primary standard a substance must be
- very pure and of exactly known composition.
- stable to storage in the atmosphere.
- soluble in titration medium (water for example).
Two examples of primary standards are Na2CO3·10H2O and H2C2O4·2H2O (oxalic acid).