Re: carbonic acid

In article <47DD7BD7.A9E36945@xxxxxxxxx>,
Mark Thorson <nospam@xxxxxxxxx> wrote:

In the scientific sense it is a glass (as are
a number of materials that do not contain silica),
but in industry a distinction is made between
glass and fused silica.

The additives have a huge impact on its properties.
For example, you can blow shapes in glass
that would be impossible in fused silica.
You can heat a piece of silica to red heat,
then plunge it into water without it cracking.

How much of the difficulty with quartz blowing arises from its high
working temperature as opposed to other problems? Certainly fused silica
tubes are formed into helical flashtubes. For all I know, simple shapes
such as flasks can be blown.

In other words is the problem with fusing silica the same as with fusing
hydrogen nuclei? It is difficult to maintain a high temperature.

Bill
.

Relevant Pages

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