Introduction
Glass is an amorphous solid that is chemically inert, often transparent but quite fragile and is used in various fields, for example, window panes, decorations, optical fiber cables etc. The molecular formula of glass is Na2O*CaO*6SiO2 , however, there are many different types of glass depending on ingredients used and their purity, for example, fused quartz is made only from SiO2 and has a higher melting point.
The ingredients needed for the production of regular glass are SiO2 (main constituent of sand), CaCO3 (limestone), Na2CO3 (soda ash) and other minor ingredients to simplify the production or to change the properties of the glass.
Task
Process
The questions:
1. What are the three main ingredients used in the production of glass ?
2. What is the molecular formula of glass ?
3. What are the three main steps of producing glass ?
4. What are some of the types of glasses and what are their uses ?
Evaluation
The answers:
1. SiO2 (main constituent of sand), CaCO3 (limestone) and Na2CO3 (soda ash);
2. Na2O*CaO*6SiO2;
3. step 1 - fusion of raw material ( all of the ingredients are ground, mixed together and heated to high temperatures (~1000°C) ).
step 2 - working with molten mass ( the liquid glass is allowed to cool a bit and is shaped as needed ).
step 3 - annealing ( slowly and carefully cooling the glass ).
4. Soda glass - used in window panes and bottles;
Pyrex glass - used in laboratory glassware;
Quartz glass - used in electrical bulbs and optical instruments;
Flint glass - used in optics;
Hard glass - used in hard glass apparatus;
Borosilicate glass - used in baking dishes, laboratory glassware and pipelines.
Conclusion
Thank you for your attention !
We hope that this material has helped you better understand the production of glass and its usage.
Credits
video source : https://www.youtube.com/watch?v=-z1P2cK9Rro "Glass making - Industry process - Chemistry" by Elearnin.