When is molarity equal to normality

In the kitchen, it may be okay to categorize solutions as weak or strong, but this is not enough in a laboratory.

The concentration of a solution determines how the molecules in the solution will collide with each other and thus, it determines the conditions for equilibrium and the reaction rates. There are many ways to define the concentration of solutions. The most commonly used amongst them are normality and molarity. What is Normality? Normality refers to the gram equivalent of the substance being dissolved in one liter of the solution.

Normality is the most preferred form of measuring concentration for titration calculations. It measures the chemical concentration determined by the chemical reaction being studied. This unit of measurement is not used for all reactions. One of the reasons why it is rarely used is because Normality is calculated on the basis of gram equivalent weight. This is determined by the number of ions that react in a reaction.

It could change on the basis of the type of reaction taking place. Thus, gram equivalent weight is not constant. In turn, this can cause confusion. Normality is used to measure:. Redox reactions. In such reactions, transfer of electrons takes place and atoms undergo reduction. Normality indicates the number of electrons that can be accepted or donated by an oxidizing or reducing agent.

Develop and improve products. List of Partners vendors. Share Flipboard Email. Todd Helmenstine. Todd Helmenstine is a science writer and illustrator who has taught physics and math at the college level.

He holds bachelor's degrees in both physics and mathematics. Updated November 06, Featured Video. Cite this Article Format. Helmenstine, Todd. What is the Difference Between Molarity and Molality? Calculating Concentrations with Units and Dilutions. Calculating the Concentration of a Chemical Solution. How to Calculate Normality Chemistry.

List of the Strong Acids and Key Facts. How to Calculate the pH of a Weak Acid. Your Privacy Rights. For example, a solution of 1M of sodium chloride dissolved in water has a molarity of 1M.

Number of moles of solute can be calculated by dividing mass by the molecular weight of the solute. For example, if you want to prepare a 1M of potassium sulphate solution, Normality is a measure of concentration that is equal to the gram equivalent weight of solute per litre of solution.

For example, 1M of hydrogen chloride gives 1M of hydrogen ions and 1M of chloride ions into the solution. Therefore, normality of hydrogen ions will be 2N for a sulphuric acid solution. For chloride ions, the normality is 2N because 1M of calcium chloride yields 2M of chloride ions. So it is like calcium can take place of two hydrogen ions.