We call normality the relationship between the gram equivalent of the solute and the volume of the solution.

The unit is represented by the letter N (normal). It is out of use, but can still be found on some labels in the labs.

Where:

N = normality (N)

no_{Equ1} = number of gram equivalent of solute

V = solution volume

How to calculate the gram equivalent?

For acid:

Where**: **

1 AND_{acid} = 1 gram equivalent of acid

MM = molar mass

Example:

How many grams is 1E (one gram equivalent) of HCl?

For base:

Where:

1 AND_{base} = 1 gram equivalent of base

MM = molar mass

Example:

How many gram equivalents are there in 80g NaOH?

For salt:

Where:

1 AND_{salt} = 1 gram equivalent of salt

MM = molar mass

Example:

How many grams is 1E of NaCl?

Summing up the three formulas, the gram equivalent can be given by:

Where:

MM = molar mass

x = H + no, OH- no or total electron transferred

Some relations between normality, molarity and mass:

Calculation example involving normality:

What is the mass of sulfuric acid (H_{2}ONLY_{4}) contained in 80mL of your 0.1N solution?

Dice:

MM = 98g / mol

V = 80mL = 0.08L

N = 0.1N

m_{1}= ?

Calculate the gram equivalent:

Calculate the mass: