Guide
1
equivalents, and the equivalent weight is usually determined either by analysis of the compounds, either on the basis of the replacement of one element by another.It is not difficult to understand that for the determination of equivalent (or equivalent weight) of the element does not necessarily come from its compounds with hydrogen.Equivalent (equivalent weight) can be exactly calculated from the element composition of the compounds with any other equivalent (equivalent weight) is known.
2
example.When the compound 1.50 g of sodium chloride formed with an excess of 3.81 grams of sodium chloride.Need to find an equivalent weight of sodium and its equivalent, if
it is known that chlorine is the equivalent weight of 35.45 grams / mol.Reshenie.Is subtracted from the total weight of the product formed the original weight of sodium.Thus
, 3, 81 - 1, 50 = 2, 31
3
That is, in the formed product (in your case sodium chloride) 1.50 grams 2.31 grams of sodium chloride is necessary.It follows that knowledge equivalent weight of chlorine (35, 45 gram / mol), you can easily find an equivalent weight of sodium by the following formula:
35, 1 x 45 50/2 31 equivalent weight of sodium is found to be 23.0 g /mol.
4
molar mass of sodium will also be equal to 23.0 grams / mole.It follows that is equivalent to one mole of sodium (as the molar equivalent weight of sodium, and the same).
5
concept of equivalent mass and equivalent also applies to complex substances.The equivalent of a compound is called the amount which reacts evenly with one equivalent of hydrogen.