chornedsnorkack
National Hazard
Posts: 564
Registered: 16-2-2012
Member Is Offline
Mood: No Mood
|
|
Choice of oxidants for tinder
The classic oxidant for tinder is potassium nitrate - as is the case with gunpowder and slow match.
But this is purely because nitrate is the most common oxidant found in nature.
Given a choice, which oxidants do you actually prefer for tinder?
Tinder must:
have optimal sensitivity:
NOT explode even when ignited
NOT ignite spontaneously
resist quiet spontaneous deterioration.
Potassium nitrate is the most popular nitrate for gunpowder and also tinder and slow matches because it is less soluble and therefore less hygroscopic
than the other common nitrates - sodium, magnesium, calcium, ammonium:
KNO3 - 316 g/l @ 20C, 101 g/mol, 3,1 mol/l
NaNO3 - 912 g/l @ 25C, 85 g/mol, 10,7 mol/.
Ca(NO3)2 - 1212 g/l @ 20 C, 164 g/mol, 7,4 mol/l
Mg(NO3)2 - 710 g/l @ 25 C, 148 g/mol. 4,8 mol/l
NH4NO3 - 1500 g/l @ 20 C, 80 g/mol, 18,7 mol/l
Now, heavy alkali are different:
RbNO3 - 650 g/l @ 25 C, 147 g/mol, 4,4 mol/l
CsNO3 - 230 g/l @ 20 C, 195 g/mol, 1,2 mol/l
but since Cs is rare, this makes CsNO3 gunpowder inconvenient to produce.
But looking for other oxidant anions...
KBrO3 - 69 g/l @ 20 C, 167 g/mol, 0,41 mol/l
KClO3 - 81 g/l @ 25 C, 122 g/mol, 0,66 mol/l
KClO4 - 15 g/l @ 25 C, 138 g/mol, 0,11 mol/l
KIO3 - 91 g/l @ 25 C, 214 g/mol, 0,42 mol/l
KIO4 - 4,2 g/l @ 20 C, 230 g/mol, 0,018 mol/l
KMnO4 - 76 g/l @ 25 C, 158 g/mol, 0,48 mol/l
So, which of these give tinder of correct sensitivity and stability?
|
|
|
njl
National Hazard
Posts: 609
Registered: 26-11-2019
Location: under the sycamore tree
Member Is Offline
Mood: ambivalent
|
|
| Quote: |
KBrO3 - 69 g/l @ 20 C, 167 g/mol, 0,41 mol/l
KClO3 - 81 g/l @ 25 C, 122 g/mol, 0,66 mol/l
KClO4 - 15 g/l @ 25 C, 138 g/mol, 0,11 mol/l
KIO3 - 91 g/l @ 25 C, 214 g/mol, 0,42 mol/l
KIO4 - 4,2 g/l @ 20 C, 230 g/mol, 0,018 mol/l
KMnO4 - 76 g/l @ 25 C, 158 g/mol, 0,48 mol/l
|
The reason you don't see these is because the first 5 release corrosive products on decomposition while the last releases toxic and staining
compounds.
Reflux condenser?? I barely know her!
|
|
|
clearly_not_atara
International Hazard
Posts: 2800
Registered: 3-11-2013
Member Is Offline
Mood: Big
|
|
I hear you'll get lots of matches with potassium ferrate 
|
|
|
Aloesci
Harmless
Posts: 28
Registered: 7-4-2018
Member Is Offline
Mood: No Mood
|
|
If you want to get even more toxic, how about tinder with K2Cr207?
|
|
|
MineMan
International Hazard
Posts: 1014
Registered: 29-3-2015
Member Is Offline
Mood: No Mood
|
|
For tinder I like my opening line to be something of the sort “let’s have 8 kids, pick the best two, and give the rest away, we get the fun of
making them and the gift of giving”
|
|
|
chornedsnorkack
National Hazard
Posts: 564
Registered: 16-2-2012
Member Is Offline
Mood: No Mood
|
|
K2Cr2O7: 130 g/l @ 20 C, 294 g/mol, 0,44 mol/l. Seems stable to moisture.
|
|
|
Herr Haber
International Hazard
Posts: 1236
Registered: 29-1-2016
Member Is Offline
Mood: No Mood
|
|
Look beyond gunpowder: fireworks
I remember seing a few interesting conversations about the use of alternative oxidizers for pyrotechnics right here on SM.
The spirit of adventure was upon me. Having nitric acid and copper, I had only to learn what the words 'act upon' meant. - Ira Remsen
|
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
