Foeskes
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Manganese dioxide flammable?
Apparently manganese dioxide is flammable? According to Wikipedia it has a flash point of 535 C, which is when it decomposes.
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woelen
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It is not flammable. If the wiki page says so, then that page is in error.
It can support or intensify certain types of fire though. It is an oxidizer.
[Edited on 13-9-17 by woelen]
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symboom
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Tin(II) oxide burns in air with a dim green flame to form SnO2.
2 SnO + O2 → 2 SnO2
Reminds me of wikipedia tin 2 oxide
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vmelkon
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Flammable means something combines with oxygen and produces a plasma (fire) and the end product are gases.
Flash point means that a liquid or gas (probably a gas) is hot enough to spontaneously burn.
MnO2 doesn't have a flash point. It isn't flammable. I looked at the wikipedia page. That's just stupid.
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VSEPR_VOID
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Generally ionic compounds are not flammable
Within cells interlinked
Within cells interlinked
Within cells interlinked
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Metacelsus
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Strictly speaking, that is true, since flammable refers to liquids with flash point below 100 °F (at least according to the NFPA), and most ionic
compounds are solids at room temperature.
(Combustible refers to solids.)
However, many ionic compounds will burn. Examples: KH, FeS2, LiAlH4, CaC2, NaNH2, Hg(SCN)2,
tetraethylammonium chloride
[Edited on 9-26-2017 by Metacelsus]
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Deathunter88
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Quote: Originally posted by vmelkon  | Flammable means something combines with oxygen and produces a plasma (fire) and the end product are gases.
Flash point means that a liquid or gas (probably a gas) is hot enough to spontaneously burn.
MnO2 doesn't have a flash point. It isn't flammable. I looked at the wikipedia page. That's just stupid. |
What you said about flash point isn't technically correct. Flash point is the temperature in which the solid or liquid gives off enough vapor in a
container to create a brief "flash" when ignited. The flame point is the temperature where the solid or liquid gives off enough vapor to sustain a
continued flame (this is usually just a bit higher than the flash point). What you are talking about is the autoignition temperature, the temperature
at which a fuel/air mixture of the substance will spontaneously ignite without a direct ignition source. This is not at all correlated with the flash
point or the flame point. For example, gasoline has a very low flash point but a high autoignition temperature, hence the need for spark plugs. Diesel
on the other hand has a high flash point but a low autoignition temperature, which is why diesel engines have no spark plugs.
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Deathunter88
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| Quote: Originally posted by Metacelsus | Strictly speaking, that is true, since flammable refers to liquids with flash point below 100 °F (at least according to the NFPA), and most ionic
compounds are solids at room temperature.
(Combustible refers to solids.)
However, many ionic compounds will burn. Examples: KH, FeS2, LiAlH4, CaC2, NaNH2, Hg(SCN)2,
tetraethylammonium chloride
[Edited on 9-26-2017 by Metacelsus] |
Your definition of combustible is incorrect. Back when chemicals were labeled according to OSHA regulations, a flammable liquid is a liquid with a
flash point below 37.8 degrees celsius, while a combustable liquid is a liquid with a flash point above 37.8 degrees celsius. However, with the
introduction of the globally harmonized system for classification of chemicals (GHS), liquids are now classed into 4 separate categories.
Danger! Extremely flammable liquid and vapor: Flash point < 73°F(23°C) and initial boiling point < 95°F(35°C)
Cat. 1
Danger! Highly flammable liquid and vapor: Flash point < 73°F(23°C) and initial boiling point > 95°F(35°C)
Cat. 2
Warning! Flammable liquid and vapor: Flash point ≥ 73°F(23°C) and < 140°F(60.5°C)
Cat. 3
Warning! Combustable liquid: Flash point > 140°F(60.5°C) and < 199.4°F(93°C)
Cat. 4
Please do your best to familiarize yourself with these definitions, nothing make me more angry than someone calling diesel "flammable" or ethanol
"combustable"!
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