Many chemicals are available in liquid rather than solid form. Liquid chemicals are easier to use and measure than solids, especially since solids are generally available in powder form. However, the stoichiometry for chemical reactions becomes more complicated in liquid form. Stoichiometry in calculations uses the amount of a substance that is included in the equation. The liquid used as the solvent does not react and the stoichiometry does not take the liquid into account in the reaction. The amount of reacting substance can be determined by finding the normality of the solution. Use the following tips to learn to calculate normality.
Step
Step 1. Gather information about the equivalent weight of the reactants
Refer to chemistry reference books to find the valence and molecular weight of the substance in question. Molecular weight is the ratio of the mass of 1 molecule of a substance to the mass of one molecule of carbon-12 divided by 12. Valence is determined by the maximum number of valence subatomic or interatomic bonds that can be formed with other substances. This information is needed to determine normality.
Step 2. Find the equivalent weight of the substance
The equivalent weight of a substance is equal to its molecular weight divided by its valence.
Step 3. Calculate normality
Normality is the concentration of the substance in question in solution. Therefore, normality is a property of the mixture, and its value varies depending on the amount of solvent in the solution of the substance in question. Normality is the number of grams of the substance in question divided by the product of the equivalent weight and the amount of solvent.
Step 4. See the following example
Dissolve sodium chloride (NaCl) in water. Sodium chloride has a valence number of 1 and a molecular weight of 58,443. Therefore, its equivalent weight is 58,443/1 or equal to 58,443.1 1 gram of NaCl is dissolved in 0.05L of water so that the normality of the solution is 1/(58, 443 x 0.05) or equal to 0.342.
