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beeludwig
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Sulfur experiment ideas
Hey guys,
The previous science teacher left a giant jar of sulfur. The stuff is pretty cheap, not sure what to do with it. Any cool ideas you think my students
would enjoy?
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j_sum1
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Off the top of my head.... I am thinking high school students here.
Reaction with metals. Al, Zn powder. There are other options too.
Polysulfides. Dissolve in NaOH.
Allotropes. Make plastic sulfur.
Burn in air. Nice blue flame. Dissolve SO2 gas in water. Watch indicator change.
Make FeS. This is a classic.
Recrystallise from toluene or xylene. With temperature control you could aim for both monoclinic and rhombic crystals.
Use as a booster in a thermite reaction and get elemental Si from sand.
Make black powder.
Make sulfur monochloride S2Cl2. This can be done at small scale if you have the ability to work with Cl2.
That's a start at least.
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beeludwig
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Black powder? ROFL. When was the last time you were in a school. Ya’all going get me fired
Seriously though those are awesome suggestions
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j_sum1
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A teacher I used to work with got students to maKe gunpowder
quite regularly.
I don't know the exact mix used and the final product was very coarse so not very potent. But, yeah: a regular thing.
Edit
I was in school today. Been teaching over 20 years. But not teaching chem at the moment.
[Edited on 17-5-2019 by j_sum1]
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beeludwig
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Sorry if that came across as dismissive. I didn’t mean to sound that way. I was just trying to imagine my AP’s face if she found out I was helping
students make black powder. She would have a conniption for sure.
[Edited on 17-5-2019 by beeludwig]
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j_sum1
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Yeah. I think it is funny too.
Video in my sig shows a variant of a polysulfide experiment. Not that dramatic but interesting and might be a seed for more ideas.
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Herr Haber
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It depends how old your students are I'd say.
You can melt sulphur and pour it in water to make beads for a collar (Mother's day anywhere?) with kids.
I wouldnt suggest making S2Cl2 with those same kids...
It depends on how you feel about H2S but you might want to pour an acid over that FeS J_sum suggests. The smell of rotten eggs is a sure way to get
kids interest.
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beeludwig
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They're high school level, but I hadn't heard of the Bead thing before. I did do some research into sulfur allotropes so I did know that it could be
plasticised but so that's a cool idea.
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sodium_stearate
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Mix it with some paraffin and heat it.
That gives off hydrogen sulphide gas.
We used to do that in the back of the highschool
chem. lab in winter when it was -20 F outside.
They'd throw open the windows.
"Opportunity is missed by most people
because it is dressed in overalls and it
looks like work" T.A. Edison
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clearly_not_atara
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I like the silicon thermite idea. Students hear a lot about silicon but they rarely ever see a piece of it. Extracting it from sand is pretty cool.
CSU Bakersfield made a write-up for classroom use:
https://www.csub.edu/chemistry/_files/Sulfur%20thermiteAO.pd...
The experiment should probably be performed by a teacher rather than the students to avoid anyone inhaling H2S.
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CharlieA
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Why is it that a chemistry teacher can't figure out what to do (safely; not too exotically) with the sulfur? (This comment is from an ex-teacher of
high school/advanced placement chemistry. I don't mean to knock the original poster, but it seems to me that the inclination of people today is
immediately post their question on a forum on-line, rather that to do any kind of research into their question on their own. I don't know if people
today are too lazy or don't know how to research a question on their own. Ok, please forgive an old fart for this rant.
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j_sum1
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I think I can probably enlighten you there, Charlie.
Most (good) science teachers are constantly on the prowl for good experiments and demonstrations. Just because you research an experiment does not
mean that it trranslates well to the classroom. Some are simply too technical, do not have easily observed variables, occur too quickly or too
slowly, are impractical for equipment reasons or the outcomes are too unreliable. Maybe they don't scale well. Or maybe there are other factors that
mean they simply do not work well with a group of teenagers. This means that there is no substitute for sharing ideas and experiences. Add to that
and beeludwig admitted that he was new to the role and was looking for ways to effectively use what had been left by his predecessor.
I think asking is probably the best place to start and is likely to lead to more creative ideas -- ones that have also been tried and tested. This is
sensible.
The truth is that in education there is no shortage of resources a couple of mouse clicks away. But sifting through these for what is actually
suitable or usable can be really time-consuming. There is a lot of junk out there as well.
@beeludwig: I don't have them on hand just at the moment but I have some scans of some really nice books of chemistry demos. Most are pitched at
undergrad level but there are quite a few that I have used in the classroom. And all are dramatic and memorable. I will post these here at my next
opportunity.
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Chemi Pharma
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I liked the idea of make Gunpowder. I did that at my school as a volcano experiment. It was awesome to everyone, even for the teacher!
Here's the formula:
12% sulfur powder;
13% charcoal powder (if you don't have access to the powder, ground the charcoal you're used to make barbecues);
75% sodium chlorate.
This give to you a kind of gunpowder that's safer than those made with potassium chlorate, cause is a kind of gunpowder less potent, with nice visual
effects and lower explosive power.
You can also use sodium nitrate ( fertilizer sold as small granules at any flower shop in this hydrated form), or potassium nitrate (sold as a
fertilizer too, in this hydrated form). The anhydrous form of potassium nitrate is often regulated by Federal Agencies, cause this give a gunpowder
with even more explosive power. Nothing too difficult to be made by us, Sciencemadness guys!
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Morgan
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Maybe as a backgrounder introduce some sulfur fun facts about mining sulfur. I had forgotten all the interesting comments and links presented in this
thread if you take the time to mine it.
http://www.sciencemadness.org/talk/viewthread.php?tid=67303
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mayko
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It's probably worth mentioning that hydrogen sulfide is a powerful and insidious poison!
Igniting a small amount of zinc + sulfur is always nice (use adequate ventilation & fire precautions). The residual zinc sulfide also has nice
properties like thermochromism (turning yellow with a propane torch's heat) and phosphorescence (charge it with a blacklight and then watch it glow.
If you have a fair amount in a vial, you can charge the powder on the outside, then shake or mix it for a variety of effects)
al-khemie is not a terrorist organization
"Chemicals, chemicals... I need chemicals!" - George Hayduke
"Wubbalubba dub-dub!" - Rick Sanchez
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beeludwig
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Quote: Originally posted by j_sum1 ![](images/xpblue/lastpost.gif) | I think I can probably enlighten you there, Charlie.
Most (good) science teachers are constantly on the prowl for good experiments and demonstrations. Just because you research an experiment does not
mean that it trranslates well to the classroom. Some are simply too technical, do not have easily observed variables, occur too quickly or too
slowly, are impractical for equipment reasons or the outcomes are too unreliable. Maybe they don't scale well. Or maybe there are other factors that
mean they simply do not work well with a group of teenagers. This means that there is no substitute for sharing ideas and experiences. Add to that
and beeludwig admitted that he was new to the role and was looking for ways to effectively use what had been left by his predecessor.
I think asking is probably the best place to start and is likely to lead to more creative ideas -- ones that have also been tried and tested. This is
sensible.
The truth is that in education there is no shortage of resources a couple of mouse clicks away. But sifting through these for what is actually
suitable or usable can be really time-consuming. There is a lot of junk out there as well.
@beeludwig: I don't have them on hand just at the moment but I have some scans of some really nice books of chemistry demos. Most are pitched at
undergrad level but there are quite a few that I have used in the classroom. And all are dramatic and memorable. I will post these here at my next
opportunity. |
Thanks J_sum. You said that perfectly. Charlie, I did do some research nor am I wholly ignorant of sulfur chemistry but I couldn't
have said it better than J_Sum. As you well know there's a vast difference between doing a chemical reaction and translating that into a concrete
learning objective. In all your years of teaching you didn't talk to peers about interesting ideas or fun projects? Welcome to the 21st century
version of networking. I'm *always* looking for new and interesting ideas. And if you have something meaningful to contribute I'm excited to hear
from an experienced educator.
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DavidJR
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That's true, only make very small quantities. Also, in higher concentrations it (temporarily) kills your sense of smell, so if you can still smell it,
you're probably safe. If you can't smell it, it could mean that there either isn't any around or that there's a dangerous amount around.
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Morgan
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Tidbits
https://en.wikipedia.org/wiki/Sulfur#/media/File:Io_highest_...
Mountain of sulfur
https://cen.chempics.org/post/116679929484/sulfur-mountain-c...
A collapse that killed the driver, what a way to go.
http://www.sulphuric-acid.com/techmanual/Plant_Safety/Sulphu...
http://www.sulphuric-acid.com/techmanual/Plant_Safety/Sulphu...
Flowers of sulfur
http://media.gettyimages.com/photos/sulfur-souvenir-made-by-...
Souvenirs
https://www.pomortzeff.com/photos/story/2011/sulphur/ijen_mi...
https://www.bcmtouring.com/forums/attachments/bcmt-dsc_8658-...
https://www.pomortzeff.com/photos/story/2011/sulphur/ijen_st...
[Edited on 19-5-2019 by Morgan]
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fusso
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That. must be called a sulflower.
(There's also a compound called sulflower)
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Simoski
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Take 500mg finely ground sulfur and mix gently with 500mg finely ground potassium chlorate using the diaper method, then take your 1 gram and wrap it
in tinfoil a few times. Take the kids outside and hit it with a hammer hard... Tell them to expect a loud bang before hand
8 )
[Edited on 19-5-2019 by Simoski]
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phlogiston
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Quote: Originally posted by Chemi Pharma ![](images/xpblue/lastpost.gif) | I liked the idea of make Gunpowder. I did that at my school as a volcano experiment. It was awesome to everyone, even for the teacher!
Here's the formula:
12% sulfur powder;
13% charcoal powder (if you don't have access to the powder, ground the charcoal you're used to make barbecues);
75% sodium chlorate.
This give to you a kind of gunpowder that's safer than those made with potassium chlorate, cause is a kind of gunpowder less potent, with nice visual
effects and lower explosive power.
You can also use sodium nitrate ( fertilizer sold as small granules at any flower shop in this hydrated form), or potassium nitrate (sold as a
fertilizer too, in this hydrated form). The anhydrous form of potassium nitrate is often regulated by Federal Agencies, cause this give a gunpowder
with even more explosive power. Nothing too difficult to be made by us, Sciencemadness guys! |
This is incorrect, and even dangerous.
- Mixtures with chlorate and sulfur are known to self-ignite during storage. Avoid them at all costs.
- Your suggestion that the mixture is a kind of less potent gunpowder that is much safer is incorrect. It is much more sensitive to friciton than the
mixture with potassium nitrate, and more 'powerful'.
- sodium chlorate is extremely hygroscopic, so generally a poor choice for pyrotechnic mixtures.
[Edited on 20-5-2019 by phlogiston]
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Chemi Pharma
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Quote: Originally posted by phlogiston ![](images/xpblue/lastpost.gif) | Quote: Originally posted by Chemi Pharma ![](images/xpblue/lastpost.gif) | I liked the idea of make Gunpowder. I did that at my school as a volcano experiment. It was awesome to everyone, even for the teacher!
Here's the formula:
12% sulfur powder;
13% charcoal powder (if you don't have access to the powder, ground the charcoal you're used to make barbecues);
75% sodium chlorate.
This give to you a kind of gunpowder that's safer than those made with potassium chlorate, cause is a kind of gunpowder less potent, with nice visual
effects and lower explosive power.
You can also use sodium nitrate ( fertilizer sold as small granules at any flower shop in this hydrated form), or potassium nitrate (sold as a
fertilizer too, in this hydrated form). The anhydrous form of potassium nitrate is often regulated by Federal Agencies, cause this give a gunpowder
with even more explosive power. Nothing too difficult to be made by us, Sciencemadness guys! |
This is incorrect, and even dangerous.
- Mixtures with chlorate and sulfur are known to self-ignite during storage. Avoid them at all costs.
- Your suggestion that the mixture is a kind of less potent gunpowder that is much safer is incorrect. It is much more sensitive to friciton than the
mixture with potassium nitrate, and more 'powerful'.
- sodium chlorate is extremely hygroscopic, so generally a poor choice for pyrotechnic mixtures.
[Edited on 20-5-2019 by phlogiston] |
You're absolutely wrong!
I Challenge you to show here to us any study or research telling about "the mixture of sodium chlorate and sulfur are known to self-ignite during
storage", like you've said.
I made this mixture over more than 5 years and none incident occurred. i've used it in a lot of pyrotechnical events, even in the school and outside,
in artists presentations. Even storing for more than one year the powder, I hadn't any accident. The only incident that occurs were when I mixtured
Ammonium nitrate to it, and it got self ignited after one month, but not before I felt a strong smell of hydrazine in the mixture, became worried and
stored it away apart from other chemicals inside a safe steel cabinet alone. Cause this the fire in that ocasion were quickly controlled. It looks
like ammonium nitrate reduced itself in contact with sulfur to some kind of hydrazine compound, cause I recognize that smell anywhere, and this make
the mixture unstable. Because this I don't recommend make gunpowder with ammonium nitrate either.
Sodium chlorate is ever solded as NaCLO3 hydrated and this is the reason this gunpowder is less potent that were made with anhydrous potassium
chlorate.
This gunpowder offers just visual effects, instead of one that were made with anhydrous potassium chlorate that's shock sensitive and very explosive.
The explosive rate of any compound is measured by the quantity of air dislocated X the velocity of dislocation, while the mixture is ignited, by
friction, heat or percussion. You'd better study more about explosives my friend, before criticize anyone here like me, with years of practice doing
that. I recommend to you read this e-book: "EXPLOSIVES", E. de Barry Barnett, you can find it on the internet, cause I tried to upload the e-book
here, but the size exceed the limit that science madness blog permits.
[Edited on 20-5-2019 by Chemi Pharma]
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fusso
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Quote: Originally posted by Chemi Pharma ![](images/xpblue/lastpost.gif) | The only incident that occurs were when I mixtured Ammonium nitrate to it, and it got self ignited after one month, but not before I felt a strong
smell of hydrazine in the mixture, became worried and stored it away apart from other chemicals inside a safe steel cabinet alone. Cause this the fire
in that ocasion were quickly controlled. It looks like ammonium nitrate reduced itself in contact with sulfur to some kind of hydrazine compound,
cause I recognize that smell anywhere, and this make the mixture unstable. Because this I don't recommend make gunpowder with ammonium nitrate either.
| Ammonium can react with S to make N2H4! Are there procedures about how to do this in a small scale?
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phlogiston
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Quote: Originally posted by Chemi Pharma ![](images/xpblue/lastpost.gif) |
You're absolutely wrong!
I Challenge you to show here to us any study or research telling about "the mixture of sodium chlorate and sulfur are known to self-ignite during
storage", like you've said. |
That is not a challenge.
R. Lancaster, Fireworks principles and practice.
3rd edition, page 32:
"Yet, when mixed together, sulphur-potassium chlorate is unstable and is liable to ignite spontaneously or to detonate at the slightest frictional
provocation."
Nearly every semi-modern book on pyrotechnics has warnings on the use of chlorate, and especially about chlorate and sulfur.
Just another one for good measure:
J.A. Conkling, Chemistry of pyrotechics, page 56
"Potassium chlorate compositions are quite prone to accidental ignition, especially if sulfur is also present."
It is good practice even not to combine mixtures with chlorate and mixtures with sulfur in one piece of fireworks where they might contact each other
(e.g. burst charge and stars in a shell).
Nobody will mention sulfur + sodium chlorate, btw, because sodium chlorate hardly ever used due to its extreme hygroscopicity.
Quote: | I made this mixture over more than 5 years and none incident occurred. i've used it in a lot of pyrotechnical events, even in the school and outside,
in artists presentations. Even storing for more than one year the powder, I hadn't any accident. |
I hope your luck lasts.
Quote: | The only incident that occurs were when I mixtured Ammonium nitrate to it, and it got self ignited after one month, but not before I felt a strong
smell of hydrazine in the mixture |
Ammonium compounds + chlorate is also a well known evil combination!
Ammonium chlorate will form, which is dangerously unstable, as you found out.
What you smelled was probably ClO2, not hydrazine.
Quote: | Sodium chlorate is ever solded as NaCLO3 hydrated and this is the reason this gunpowder is less potent that were made with anhydrous potassium
chlorate. |
You mean wet? (I don't think it forms hydrates. I've never heard of them, and can't find anything about them.)
Sure, that will slow it down. If you use sodium chlorate, 'fortunately' it will stay wet.
The wet compositions will also erode metals, and the contamination from some metals (for instance copper) can dramatically worsen the
sensitivity/spontaneous ignition problems.
Potassium chlorate-based mixtures will dry out.
Quote: | You'd better study more about explosives my friend, before criticize anyone here like me, with years of practice doing that. |
If you had read as much as I have, you would not have to 'challenge' me to find references for well known facts.
Quote: | I recommend to you read this e-book: "EXPLOSIVES", E. de Barry Barnett, you can find it on the internet, cause I tried to upload the e-book here, but
the size exceed the limit that science madness blog permits. |
It is interesting, but outdated. It is literally about a century old, and insights on good and bad (safe/unsafe) practices have changed in the
meantime. Maybe you can have it added to our library (see the link at the science madness home page
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"If a rocket goes up, who cares where it comes down, that's not my concern said Wernher von Braun" - Tom Lehrer
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Morgan
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I was reading this comment on this video and wondered to what degree it was applicable or something else to keep in mind aside from other variables.
(koolkitty8989)
"Not all sulfur is created equal: flowers of sulfur is sublimated which causes acid traces to be incorporated into the tiny crystals, then exposed
when broken/crushed, and that acid forms traces of chloric acid, which in turn is extremely friction and impact sensitive."
"Particularly pure powdered sulfur or that which is contaminated with alkaline compounds (particularly alkali or alkaline earth metal sulfides,
cabonates, oxides, hydroxides) may render it less reactive. (I /think/ most of the 90% gardening sulfur used for dusting has some calcium carbonate in
it for stabilization and anti-caking, and that may reduce friction sensitivity in such mixtures ... which could be good if safety is a concern, but
you very rarely mix chlorate with sulfur with that intention these days ... not with perchlorate or nitrate options)"
Potassium Chlorate with sulphur - friction detonation tests
https://www.youtube.com/watch?v=DSJwtHRmfSQ
And from Wiki
"Flowers of sulfur were traditionally produced by subliming naturally occurring sulfur, known as sulphur vivum. Impurities and moisture could cause
acid residue in the product, so it was often washed, the result being known as "washed flowers of sulfur" (in Latin, flores sulphuris loti)."
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