![Woman looking at laundry detergent.](https://img-aws.ehowcdn.com/360x267p/cpi.studiod.com/www_ehow_com/photos.demandstudios.com/getty/article/178/120/76765409_XS.jpg)
Sodium carbonate, also known as washing soda, is a common ingredient in laundry detergents. When dissolved in water, it tends to form solutions with pH values between 11 and 12.
Water
![Photo Credit: DamianPalus/iStock/Getty Images Close up of water.](https://img-aws.ehowcdn.com/600x600p/cpi.studiod.com/www_ehow_com/photos.demandstudios.com/getty/article/250/173/160102125_XS.jpg)
Water, H?O, undergoes a process known as autodissociation, in which it separates into a hydrogen ion (H?) and a hydroxide ion (OH?):
H?O ? H? + OH?
pH
![Photo Credit: deyangeorgiev/iStock/Getty Images Litmus paper in solution testing the pH.](https://img-aws.ehowcdn.com/600x600p/cpi.studiod.com/www_ehow_com/photos.demandstudios.com/getty/article/94/36/178601118_XS.jpg)
pH is actually a measure of the amount of H? in a solution and ranges from 0 to 14.
In general terms, a pH greater than 7 indicates an alkaline (or basic) solution (more OH? than H?). A pH less than 7 indicates an acidic solution (more H? than OH?). A pH of 7 indicates a neutral solution, such as water (H? and OH? are equal).
Sodium Carbonate
![Photo Credit: Vitali Dyatchenko/iStock/Getty Images Baking soda on black background.](https://img-aws.ehowcdn.com/600x600p/cpi.studiod.com/www_ehow_com/photos.demandstudios.com/getty/article/217/178/122731491_XS.jpg)
Sodium carbonate (Na?CO?), also known as washing soda, produces sodium ions (Na?) and carbonate ions (CO?²?) when dissolved in water:
Na?CO? ? 2 Na? + CO?²?
The sodium ions have no influence on the pH of the resulting solution. The carbonate ions, however, are basic and make the solution alkaline by increasing the amount of OH?:
CO?²? + H?O ? HCO?? + OH?
Concentration and pH
![Photo Credit: Elena Rachkovskaya/iStock/Getty Images Adding sodium carbonate to water in a beaker is easy.](https://img-aws.ehowcdn.com/600x600p/cpi.studiod.com/www_ehow_com/photos.demandstudios.com/getty/article/64/233/137929097_XS.jpg)
The important part of pH is that it depends on concentration. That is, dissolving two tablespoons of sodium carbonate in a glass of water will result in a higher pH than dissolving one tablespoon.
Mixing Instructions
![Photo Credit: fotyma/iStock/Getty Images Blue jar with water mixture.](https://img-aws.ehowcdn.com/600x600p/cpi.studiod.com/www_ehow_com/photos.demandstudios.com/getty/article/94/51/178727406_XS.jpg)
One gram (0.035 ounces) of sodium carbonate dissolved in water and diluted to 1.0 liter (about 1 quart) will produce a solution of pH 11.37.
Five grams (0.18 ounces) of sodium carbonate dissolved in water and diluted to 1.0 liter (about 1 quart) will produce a solution of pH 11.58.
Ten grams (0.35 ounces) of sodium carbonate dissolved in water and diluted to 1.0 liter (about 1 quart) will produce a solution of pH 11.70.
References
Photo Credits
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