To perform a double displacement reaction using sodium sulphate and barium chloride solutions.
Double displacement reactions may be defined as the chemical reactions in which one component each of both the reacting molecules is exchanged to form the products. During this reaction, the cations and anions of two different compounds switch places, forming two entirely different compounds.
The general equation which represents a double displacement reaction can be written as:
Double displacement reactions generally take place in aqueous solutions in which the ions precipitate and there is an exchange of ions.
For example, on mixing a solution of barium chloride with sodium sulphate, a white precipitate of barium sulphate is immediately formed. These reactions are ionic in nature. The reactants changes into ions when dissolved in water and there is an exchange of ions in solution. This results in the formation of product molecule.
Double displacement reactions can be further classified as neutralization, precipitation and gas formation reactions.
Neutralization reactions are a specific kind of double displacement reaction. An acid-base reaction occurs, when an acid reacts with equal quantity of base. The acid base reaction results in the formation of salt (neutral in nature) and water.
Precipitation is the formation of a solid in a solution or inside another solid during a chemical reaction. This process usually takes place when the concentration of dissolved ions in the solution exceeds the solubility product.
A double displacement reaction should also occur if an insoluble gas is formed. Gases such as HCl and NH3 are soluble in water, but some other gases, such as H2S, are not soluble in water.
We may conclude that in double displacement reactions, two compound exchange ions or elements to form a new compound. The product obtained is either a gas or solid which can be separated from the reaction mixture, or a stable covalent compound, often water.
Here we will talk about the double displacement reaction between sodium sulphate and barium chloride solution.