Normality of a solution determines the concentration of solutes in the solution. It is expressed as number of equivalents per litre. (Normality = gram equivalents/ litres solution). The easiest way to find normality is from molarity. All you need to know are how many moles of ions dissociate. Normality can also be calculated by multiplying molarity with gram equivalent Normality (N) = Molarity(M) x Equivalent (N/M).
Normality is not an appropriate unit of concentration in all situations. It requires a defined equivalence factor and is not a set value for a chemical solution. The value of normality can change according to the chemical reaction under examination.
First, determine the equivalent of HCl. An equivalent is the number of moles of hydrogen ions one molecule of an acid will donate or one mole of base will accept.
Equivalent of HCl= 1 (as each molecule of HCl will donate only one mole of hydrogen ion)
For example, let's consider 2M solution of HCl.
Gram equivalent of HCl is 1 Normality (N) = Molarity(M) x Equivalent(N/M) Normality = 2 x 1= 2N
For all solutions which have gram equivalent value of 1, the normality of the solution is always equal to the molarity of the solution.
About the Author
Nitu Bansal has been contributing to scientific journals since 2005. She has published peer reviewed scientific articles, as well as review articles. Her work has appeared in "Current Pharmaceutical Biotechnology," the website Pub Med, and many other print and online publications. Bansal has a Doctor of Philosophy in biochemistry from New Jersey Medical School and works for the Cancer Institute of New Jersey.