busukxuan
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Can MnO2 catalyse decomp. of liquid KNO3?
Can MnO2 catalyse decomposition of liquid KNO3?
Is the decomposition mild or vigorous?
[Edited on 8/12/11 by busukxuan]
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blogfast25
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Fusing MnO2 with KOH and KNO3 leads to the formation of potassium manganate (KMnO3, Mn (VI), green), not to be confused with potassium
permanganate.
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busukxuan
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Nope I'm not asking for that. I'm asking if MnO2 can catalyze decomposition of molten KNO3 like it does to H2O2, and if the reaction is vigorous.
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hissingnoise
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Sounds like something to try on a very small scale - just in case . . .
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busukxuan
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Surprisingly, it is what i plan to contribute to the chemistry society of my school. That might be dangerous so I'm only using a few grams of KNO3 in
a test tube and add only a tiny amount of MnO2(that is like a pile of dust that takes only 0.5 cm^2 of area). But I have to make sure before I submit
the experiment, so help~. I came up with that idea because I realised that our school's lab probably doesn't have 30% H2O2. I want to put a small
candle above the test tube to show that it is oxygen, so the gas must be produced fast enough to make a visible effect.
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ScienceSquirrel
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Manganese dioxide does not catalyse the decomposition of potassium nitrate to form oxygen.
The best way to make oxygen is with thin bleach and hydrogen peroxide.
Take a large rigid plastic glass and add some bleach, partly cover with a beer mat and then add the peroxide down the side. Completely cover with the
beer mat and swirl gently, a vigorous reaction occurs.
Take a small candle and fix it on a piece of wire, light the candle and then plunge it into the glass, it will burn very vigorously.
Joss sticks are good, a smouldering joss stick bursts in to flame when plunged in to a glass full of oxygen. You can tell the class about the
accidents that have happened when someone has lit a cigarette in an oxygen tent.
A piece of red hot steel wool burns with a brilliant shower of sparks.
My favourite is hexamine which burns with a very tame flame in air but with a brilliant white light in pure oxygen.
The oxygen should not be inhaled as it will contain corrosive droplets from the reaction for some time.
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