What is Glass?
Glass is made from liquid sand. Unbelievable right? Glass can be made by simply heating sand. Of course that can’t be done in our domestic home since sand melts at an extremely high temperature of approximately 17000 °C.
When sand (which is mostly made of silicon dioxide) is heated to extreme temperatures, it is then allowed to cool down and be shaped into almost any form by either blowing or pouring in pre-designed molds. This extremely easy process can also be enriched with additives, which can provide glass with every color or opacity imaginable, improve quality, durability and other properties.
But it doesn’t matter how much you cool the sand, it never quite sets into a solid. Instead, it becomes a kind of frozen liquid or what materials scientists refer to as an amorphous solid.
In a commercial glass plant, sand is mixed with waste glass (from recycling collections), soda ash (sodium carbonate), and limestone (calcium carbonate) and heated in a furnace. The soda reduces the sand’s melting point, which helps to save energy during manufacture, but it has an unfortunate drawback: it produces a kind of glass that would dissolve in water! The limestone is added to stop that happening. The end-product is called soda-lime-silica glass. It’s the ordinary glass we can see all around us.
Read more about glasses here
References
- http://www.historyofglass.com/glass-making-process/how-glass-is-made/
- https://www.explainthatstuff.com/glass.html