Answered By: Library Intern
Last Updated: Nov 19, 2016     Views: 19

Take a look at the British Glass website: http://www.britglass.org.uk/Index.html and click on "About Glass" and "Types of Glass" to learn more about different types of glass and their composition. I will quote a few paragraphs from the "soda lime" section:

"Most of the glass we see around us in our everyday lives in the form of bottles and jars, flat glass for windows or for drinking glasses is known as commercial glass or soda-lime glass, as soda ash is used in its manufacture.

"The main constituent of practically all commercial glass is sand. Sand by itself can be fused to produce glass but the temperature at which this can be achieved is about 1700oC. Adding other minerals and chemicals to sand can considerably reduce the melting temperature.

"The addition of sodium carbonate (Na2CO3), known as soda ash, to produce a mixture of 75% silica (SiO2) and 25% of sodium oxide (Na2O), will reduce the temperature of fusion to about 800oC. However, a glass of this composition is water-soluble and is known as water glass. In order to give the glass stability, other chemicals like calcium oxide (CaO) and magnesium oxide (MgO) are needed. These are obtained by adding limestone which results in a pure inert glass.


"Most commercial glasses have roughly similar chemical compositions of:

70% - 74% SiO2 (silica)
12% - 16% Na2O (sodium oxide)
5% - 11% CaO (calcium oxide)
1% - 3% MgO (magnesium oxide)
1% - 3% Al2O3 (aluminium oxide)

"Within these limits the composition is varied to suit a particular product and production method. The raw materials are carefully weighed and thoroughly mixed, as consistency of composition is of utmost importance in making glass."

The website also discusses lead glass, borosilicate glass, and fiber glass. The composition of these glasses is quite different from soda lime glass.

I have attached a couple lists of books that explain more about glass and its chemistry.
 

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