Chemically, washing soda is known as sodium carbonate. It is also often referred to as soda ash or soda crystals. Washing soda is a sodium salt and is obtained from carbonic acid. It is widely available in the form of a white powder.
It is mostly found in a crystalline form as a heptahydrate (where each sodium carbonate molecule is bonded with seven molecules of water). On exposure to air, it loses the water molecules to form a monohydrate. When it dissolves in water, its molecules break down and ions of sodium and carbonate are released.
Use in Chemical Laboratories
In laboratories, this sodium salt serves as an excellent electrolyte in the electrolysis process (a chemical reaction carried out with the help of electric current). There are two main advantages of this electrolyte. Since it is a good conductor of electricity, electric current can pass through it easily.
Moreover, it is not corrosive in nature and does not cause any harm to the anode used for electrolysis. Due to its high stability, this chemical compound is often required in the quantitative analysis of acid-based solutions.
Washing soda has a significant role in the glass industry where it is used as an ingredient for manufacturing glass. Firstly, a mixture of washing soda, sand or silicon dioxide and calcium carbonate are heated at a very high temperature. Then, it is cooled down very quickly which results in the formation of glass.
In brick industry, sodium carbonate is used in the form of a wetting agent. It helps to reduce the water content in the clay and makes the task of molding the clay in the shape of a brick easier. In the dyeing industry, it is used to improve the chemical bonding between the dye and the fiber.
When it is dissolved in water, the solution acts as a fungicide that can kill mold and mildew in the damp areas of the house. Water in the swimming pools turns acidic due to repeated addition of chlorine as a disinfectant. Washing soda is added to this water to make it chemically neutral.
Washing soda is popularly used for softening hard water. We have seen that when soaps or detergents are added to hard water, no lather is formed. It happens because the calcium and magnesium ions present in the hard water react with the soap or detergent, changes its properties and prevents lather formation.
This in turn adversely affects the cleaning ability of the soap. As a result, more detergent is required to make lather. When washing soda is added to the hard water, it prevents the ions of the hard water from formation of chemical bonds and thus, enables the added detergent to clean up the dirt from clothes easily.
Sodium carbonate is important in taxidermy for preparing hunting trophies. When added to boiling water, it helps in the removal of flesh from the skulls and bones of dead animals. These hunting trophies provide a lot of information for biological and historical studies.
Washing soda acts as a strong base and can neutralize acidic effects. During the process of developing photographic films, the pH value needs to be controlled to obtain a stable alkaline condition. Here, sodium carbonate is commonly used in to regulate the pH value.
Thus, you can see that washing soda is not just used for laundry and household cleaning purpose. It has so many diverse uses mainly because sodium carbonate itself is a chemically stable compound and possesses strong alkaline properties.
While handing this chemical, you must avoid any direct contact with it as it can cause skin irritation. Moreover, make sure that it does not get into the eyes or nose.