:Oxidizing and reducing flames

{{Short description|States of a flame}}

{{more citations needed|date=March 2015}}

File:Types of oxyacetylene flames.png

A flame is affected by the fuel introduced and the oxygen available. A flame with a balanced oxygen-fuel ratio is called a neutral flame. The color of a neutral flame is semi-transparent purple or blue.{{Citation|title=HHO gas generator, Typ: H2-3 (BlackWater) 1500 L/hour| date=30 December 2015 |url=https://www.youtube.com/watch?v=TCXCpu3zSrA|language=en|access-date=2021-12-24}} This flame is optimal for many uses because it does not oxidize or deposit soot onto surfaces.File:Bunsen burner flame types.jpg flames with different oxygen levels: 1. diffusion flame, 2. reducing flame, 3. fuel-rich neutral flame, 4. neutral flame]]

{{multiple image

| align = right

| direction = vertical

| image1 = OxygenRichBlowTorchFlame.jpg

| caption1 = Oxygen rich butane torch flame

| image2 = FuelRichBlowTorchFlame.jpg

| caption2 = Fuel rich butane torch flame

}}

Oxidizing flame

If the flame has too much oxygen, an oxidizing flame is produced. When the amount of oxygen increases, the flame shortens due to quicker combustion, its color becomes a more transparent blue, and it hisses/roars.[https://books.google.com/books?id=r81z6oAOIowC&dq=%22oxidizing+flame+is%22&pg=PA413 "The Anatomy of a Flame"], in: "Jewelry concepts and technology", by Oppi Untracht, 1983, {{ISBN|0-385-04185-3}} With some exceptions (e.g., platinum soldering in jewelry), the oxidizing flame is usually undesirable for welding and soldering, since, as its name suggests, it oxidizes the metal's surface. The same principle is important in firing pottery.

Reducing flame

A reducing flame is a flame with insufficient oxygen. It has an opaque yellow or orange color due to carbon or hydrocarbons{{cite journal|title=Gas Age|journal=Gas Age: Combining Natural Gas, Gas Age, Gas Record|date=1920|volume=45|publisher=Robbins Publishing Company|issn=0096-0780|url=https://books.google.com/books?id=K6vmAAAAMAAJ|page=196|accessdate=2015-01-01}} which bind with (or reduce) the oxygen contained in the materials the flame processes. The flame is also called carburizing flame, since it tends to introduce carbon soot into the molten metal.

The flame also produces carbon monoxide, a poisonous gas which burns on the outer envelope of flame into carbon dioxide.{{Cite web|title=Combustion of fuels - Products and effects of combustion - GCSE Chemistry (Single Science) Revision - Other|url=https://www.bbc.co.uk/bitesize/guides/zx6sdmn/revision/1|access-date=2021-12-24|website=BBC Bitesize|language=en-GB}}

= Reducing flames with no carbon =

Reducing zero-carbon fuel flames, such as reducing hydrogen flames, are exceptions. They don't have an opaque yellow or orange glow, nor do they produce soot or carbon monoxide.

See also

References

{{reflist}}

Category:Fire