Nepedia
Back to Discover
Fluent Reader
⚛️

Soda–lime glass

physical science Maturity 11-13 Next article →

Soda-lime glass is the most common type of glass in the world. It makes up about 90% of all manufactured glass. You can find it in many places around you. It is used to make windowpanes for houses. It also makes containers like bottles and jars for food.

Glass milk bottles
Glass milk bottles

This glass is very important because it is inexpensive and stable. It is also quite hard and easy to shape. Scientists call it soda-lime-silica glass because of what it contains.

Making this glass is a careful step-by-step process. First, makers create a mix of raw materials called a batch. This batch includes silica, soda, and lime. They also add things like dolomite or aluminium oxide. These materials go into a large glass furnace. The heat in the furnace can reach 1675 °C.

Soda-lime window, not by float glass process
Soda-lime window, not by float glass process

The soda acts as a flux. This means it helps the silica melt at a lower temperature. Without it, silica would need much more heat to melt.

There are two main types of soda-lime glass. The first type is called flat glass. This is the kind used for windows. The second type is called container glass. This is used for bottles and jars.

Glass milk bottles
Glass milk bottles

These two types are actually made differently. Flat glass uses a method called the float process. Container glass is made by blowing or pressing. Container glass also has more chemical durability. This helps it hold liquids like drinks without breaking down.

Each ingredient plays a special role in the final product. The silica makes up about 70 to 74% of the weight. Soda, or sodium oxide, lowers the temperature needed to melt the mix. However, soda can make glass dissolve in water. To stop this, makers add lime, which is calcium oxide. They might also add magnesium oxide to help it stay strong.

Soda-lime window, not by float glass process
Soda-lime window, not by float glass process

If the raw materials have iron oxide, the glass can turn green or brown.

Soda-lime glass is great for our planet because of recycling. It can be resoftened and remelted many times. This makes it ideal for making new things from old ones. It is also easier to work with than pure silica. Pure silica is very hard to shape because it melts at 1723 °C. Soda-lime glass becomes easy to form at about 900 °C. It is a wonderful material that we use every single day.

391 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (2)
File:Glass milk bottles.jpg
Glass milk bottles.jpg
File:Soda-lime window, not by float glass process.jpg
Soda-lime window, not by float glass process.jpg
More to explore

🔬 Go deeper

More advanced topics to explore

🪜 Step back

Simpler topics to build understanding

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.