Uses of Sodium Hydrogen Carbonate (Bicarbonate of Soda)
The number of chemicals in the home abound. Chemistry is at work in the bathroom, kitchen, laundry and medicine cabinet. Sodium bicarbonate is a most useful, versatile and cheaply available substance used in the home and for personal use.
Sodium bicarbonate is obtained by chemical process called the Solvay Process, or more directly by extraction from the ore. It is mildly alkaline and has a wide range of applications.
Sodium bicarbonate has the chemical formula CHNaO3. It is known under different household names: baking soda, sodium bicarb or bicarb soda, etc. but better known to chemists as sodium bicarbonate, bicarbonate of soda, sodium hydrogen carbonate, and sodium acid carbonate.
History of Production
The ancient Egyptians first mined the natural deposit called natron, which contains mostly sodium bicarbonate. The mixture was used as a cleansing agent such as soap. It was not until 1791 in France that Leblanc artificially manufactured sodium bicarbonate as we know it today. Later, in 1846, two bakers Dwight and Church refined the process of making baking soda from sodium carbonate and carbon dioxide. The ammonia-soda process was developed into its modern form by Ernest Solvay during the 1860s.
Baking soda is mainly prepared from the Solvay Process. However, commercial quantities are also produced from soda ash of the ore trona, which is dissolved in water and treated with carbon dioxide. Sodium bicarbonate then precipitates as a solid. The main reaction is:
Na2CO3 + CO2 + H2O -> 2NaHCO3
Sodium bicarbonate has a number of interesting properties, which makes it so versatile and useful:
- Odourless, white crystalline solid or powder
- Slightly alkaline in solution
- Sparingly soluble in water
- Decomposes to sodium carbonate and carbon dioxide on heating
- Has relatively low toxicity
- The powder dust is not explosive
Applications of Baking Soda
Baking soda is a weak base and therefore not a powerful detergent compared to a strong alkali which breaks down fat. However, it does remove dirt with the properties already alluded to. In order to prevent any alkali from damaging your skin, rubber gloves should be worn.
For the Home:
- Cleaning agent – fridges, garbage disposals, etc.
- Water softener – use in washing machines and for washing dishes
- Deodorizing – shoes, footwear cupboards, carpet refresher
- Fire extinguisher – forms a smothering soapy foam
- Polishing – removes dirt without damaging high hardness materials such as stainless steel or iron
- Mixed with sugar – acts as an effective pesticide for cockroaches and silverfish
In the Kitchen:
- Baking – used as a leavening agent, the carbon dioxide generated makes the dough rise
- Cooking – quickly softens vegetables such as french beans and broccoli
For Care of the Body:
- Use as a teeth whitener – brush teeth with a paste of bicarb soda and water
- Sodium bicarbonate ear drops
- Stomach reliever – spoonful in cool glass of water
- Eczema reliever – half-cup in hot bath from 15 to 20 minutes
- Also good for the throat, painful gums, insect bites, and warts
- Use in cosmetics and personal care products
Sodium bicarbonate can neutralise or reduce acids in the blood, or urine. It may be used in emergency medical situations (heart attacks, serious kidney or lung problems) to correct the normal acid-base balance in the blood or as an aid in treating overdoses with certain types of medications.
Impurities in Sodium Bicarbonate
Sodium bicarbonate is a very versatile substance and the list of uses given is by no means exhaustive, but represents some of the better known uses. People should be aware that when using for medicinal purposes, producer’s baking soda contains traces of aluminium. P&R Labpak recommend you seek medical and/or other advice before using such a product for any kind of personal use.
- Place an open box or small open container of bicarbonate of soda in the refrigerator or pantry to absorb odours. Replace every three months.
- Eliminate odours in dishwashers by running a cycle without any dishes once a week with bicarb soda in the soap dispenser and vinegar in the rinse-aid compartment. Sprinkle a handful in the bottom of the dishwasher between loads. It will reduce odours and act as an additional cleanser for the next wash.
- Clean tannin-stained tea and coffee mugs by sprinkling some bi-carb soda on a damp cloth and rubbing gently.
- For saucepans that cannot be cleaned with scourers, add cold water and one to two tablespoons of bicarb soda. Bring to the boil and simmer for a few minutes. Empty water from pan and use a steel scourer to remove any residue (ensuring saucepan has had time to cool sufficiently to handle safely).
- To eliminate odours and reduce drain blockages, put half a cup of bi-carb soda and half a cup of vinegar down the kitchen sink drain. Leave for at least an hour then rinse with boiling water (use hot water only for plastic pipes).
Using Bicarbonate of Soda in the Laundry
- Dissolve two to three tablespoons of bicarb soda in a bucket of warm water to pre-soak cloth nappies and/or items with mould or stubborn stains. Allow to soak, then wash items in warm soapy water and dry in the sun.
- As a natural laundry whitener, use 2 teaspoons of bicarb soda in half a bucket of cold water. Soak items for 30 minutes then wash as usual.
- Add half a cup to the washing machine for the rinse cycle to keep clothing and linen fresh.
General Cleaning with Sodium Bicarbonate
- Sprinkle sodium bicarbonate into smelly sports shoes and leave for a few days to reduce foot odour.
- Make a paste with three parts sodium bicarbonate to one part water (adjust to suit individual needs). Use as an alternative to other paste cleansers.
- Sprinkle carpets with sodium bicarbonate, leave for a few minutes, then vacuum as usual to help eliminate household odours. This also works on pet bedding and car upholstery. Sprinkle and leave for 15 minutes before vacuuming.
- Freshen children’s stuffed toys by sprinkling with bicarb soda. Leave for 15 minutes, then brush off residue.