By substituting the above expression for the second expression,

we have the following expression:

Normality x milliliters = normality x milliliters

(reaction 1)

(reaction 2)

OR

N1 X ml1 = N2 X ml2

These relationships enable further calculations that may lead to

determinations of the weights of substances that react with the

standard solution.

Verify that the proper amount of solute is used at all times.

This not only aid in the accuracy of the process, but also saves

time and ensures safety. As mentioned earlier, you must ensure

that correct calculations were used to determine both the weight

of solids and volume of liquids.

The following is a step-by-step description of the process of

standardization by titration.

We are assuming that a 0.1N

solution of an acid is to be prepared and standardized.

In

addition, a quantity of 1 liter is required.

1.

Select a basic primary standard for an acidic solution,

note the milliequivalent weight and the (assay) number (this

information is usually found on the container of the substance.

2.

Calculate the weight of the primary standard required to

neutralize about 40 milliliters of 0.1N acid with the use of the

following function (where DFP is decimal fractional purity).

Weight needed (Mg) = (N) (40ml) (MEW)

DFP

3.

Weigh a clean and dry Erlemeyer flask on an

analytical

balance.

4.

Add the grams of primary standard calculated in step 2

above, and record the weight to the fourth decimal place.

5.

Dissolve the primary standard in an unmeasured quantity of

water.

6.

Add two or three drops of methyl orange.

3-5