10-foot Barking Dog - Periodic Table of Videos

[@effortless35]

2:11 "and the flame was almost stationary. Neil had time to walk away from the experiment" The professor sounds disappointed.

[@DavidWorley94]

"Neil was really scrubbing hard" *Neil's scrubbing hard face*

[@trespire]

David W That tube looked scared.

[@Tursiopstruncatus]

David W I laughed hard at that! Hahaha!

[@MossyStudios]

David W Nice Eggplant

[@mateushtommason6314]

and he blinked too

[@AndrewSteffenHB]

4:30

[@karlish8799]

Neil's expression while scrubbing that tube out made me chuckle. Doesn't look like a very happy camper there. Another great vid, Thanks!

[@brandonfesser1893]

Brady, please convey our thanks to Neil for all his hard work on this one!

[@naquiniv5930]

5:04 I feel an animated gif coming on....

[@jadeshiota784]

4:31

[@fabian0042]

Phew , it wasn't just me that noticed it

[@idnwiw]

***** ...the Dekapod we were promised in the headline

[@naquiniv5930]

WIN!!!!!

[@BongMyFishing]

Jade Shiota Yeah...

[@TimmacTR]

Neil is like the generic evil genius lab assistant to the mad scientist..

[@zes3813]

wrgg

[@pedroelerr]

hi guys, my name is Pedro H. Eller and a wanna thank you to inspire me to became a scientist chemistry :D today I was accepted in the university of Brasilia (UNB) in Brazil, you made me love chemistry haha I have been watch your videos for almost 5 years. again, thank you a lot, I hope one day that I will be able to meet you guys in England :) bye

[@dfgndfghdfghdfgh]

This is great

[@hempwick8203]

did you graduate yet? :-)

[@pedroelerr]

@@hempwick8203 yup haha

[@sammyk1155]

Pedro Eller congrats!

[@angelobonanno1859]

I came here to ask if you graduated but find out that you did Cheers man, this is prof Poliakoff's KZbin legacy

[@3800S1]

Love the oscillation, same thing happens in the intake and exhaust runners of an engine. This really helps visualize that.

[@magicalpencil]

I'd love to wake someone up with a barking dog tube

[@rams6702]

magicalpencil you are a genius

[@BlackEpyon]

magicalpencil Meanwhile.... in the dormitory of a chemistry major...

[@finerz321]

...Sir Martyn Poliakoff is.... Lighting the tube XD

[@DoiInthanon1897]

Wouldn’t that be great 😆

[@pingerty10]

2:35 "A nice voosh" 5:25 "A very deep wroom"

[@virtlink]

Great video! I especially liked the high-speed Neil mixing gases in a 10-foot tube parts. :P

[@JohnMichaelson]

Virtlink Even more amazing is that the footage isn't sped up. He's just naturally that fast!

[@trespire]

Virtlink Ever since his lab accident many years ago involving Unobtanium, Neil has special powers every time his services are required. But he doesn't like to talk about it.

[@DoiInthanon1897]

@@trespire That would reveal the hidden myth within.

[@dielaughing73]

With the iProf logo

[@bailey125]

Does Neil have emotions?

[@k.c.lejeune6613]

baileyboy125 He does not.

[@jaredkennedy6576]

I saw him giggle in one of the balloon experiments. Very brief, split second giggle, then back to serious Neil mode.

[@PlutoTheSynth]

Jared Kennedy GIVE ME THE LINK

[@Aetohatir]

He's the lab robot. They do not get programmed with emotion.

[@SuperSchnitzel25]

I guess his emotions during chemical experiments are mixed up

[@Saturn_Sky99]

The barking dog is one the most extraordinary things I've actually ever seen

[@X0verXDriveX]

I'm not sure Neil gets enough credit for his work. This man makes "the magic" happen and I think he deserves a big and long standing ovation. Thank you Neil!

[@Tigermoto]

+X0verXDriveX email him LOL

[@hrdragovoljac]

The Neil is real. Neil is coming. All hail the Neil.

[@q23main]

Oh man. I would like to hear that second day experiment live :)

[@brayanrodriguez1085]

This man is science! I feel smarter every time I watch any of his videos :D

[@HDInstrumental1]

The sound it makes is soooo cool!

[@darwn977]

I dont understand why its called the barking dog. It should be called the farting dinosaur.

[@quangvasot]

or moaning whale

[@hokiepokie333_CicadaMykHyn]

Try this with 15 gallons of diethyl ether, at a canine shelter... You'll quickly learn.

[@mugdha_desh1124]

😂🤣

[@mattlogue1300]

Yeah it'd be funny if dogs were there. They'd be like WTF

[@geniusdude8975]

Lamao

[@JustOneAsbesto]

I just flew in from Los Angeles and BOY ARE MY DOGS BARKIN'.

[@Natecx]

JustOneAsbesto looks like your facial hair flew in from LA too :p

[@darcgibson5099]

JustOneAsbesto I like your name. Really inspiring, actually.

[@Deemooo]

What would happen if you use a tube with an irregular shape? Would it affect the sound and the motion of the flame? It would be really interesting to watch (yet really expensive to get a custom made tube).

[@Jack2Japan]

Another fine video by Brady and the Professor (i.e., Sir Martin).

[@andrewkovnat]

Jack2Japan That's Sir Doctor Professor Martin to you sir.

[@jimm3205]

Anyone else notice how much Peter sounds like Nigel Tufnel - legendary and adequate guitar player for Spinal Tap? When I need my blood pressure lowered, I just have to listen to either him or Sir Martyn speak. Quite soothing to the ears!

[@cjsmith411yt]

Sir Poliakoff commented toward the end on how they'd learned from this that larger mixtures require more thorough mixing. It immediately struck me, in a practical application, that this explains why baking recipes often don't scale up to mass production very well.

[@mreueujj1]

2:20 That look of: "I'm the one who's gonna have to clean this"

[@siyacer]

Yep

[@brothyr]

Does it sound better in real life? I think the microphone on the camera capped off on the sound being so loud.

[@coopergates9680]

I think such a long tube would achieve superior results when horizontal, because when it's vertical, the CS2 vapors collect towards the bottom because they're much denser (over 76 g./mol). What is the advantage of N2O over O2 for this reaction?

[@TheBeetrootman]

4:34 Neil's face. So serious.

[@Squat5000]

I love how you guys burned the ceiling... This is ABSOLUTELY the best video on this I have seen.

[@wavysheep]

I've been subscribed to this channel for over 2.5 years not once have I watched your videos . . . But now that I'm watching it I actually really enjoy it

[@periodicvideos]

Dress Mann ummm, I think that's good?

[@TheZabbiemaster]

+Periodic Videos Dear Periodic Videos, Wouldn't adding a catalyst solve the problem of the slow moving flame?

[@u.v.s.5583]

A nice catalyst to try could be 2,4,6-trinitrotoluene in nice, large bricks.

[@scififanman]

Very cool vid. Thanks Neil for all the hard work!

[@Jujudo]

Imagine if you had a 100m long tube barking dog going from one side of you to the other, with you standing at the 50m mark The sound would be like the loudest motorbike ever going past you

[@yaldabaoth2]

Knoledge Whale Let's rip out all the unnecessary stuff from the LHC and make it the world's largest barking dog tube.

[@possumverde]

***** The majority of the sound comes from the open end (which is why the length affects the pitch.) If you were standing 50m from the opening, you'd probably only hear a very low pitch "bark" that more or less remained at the same volume level...Now that I think about it, 100m might be long enough to create a pitch below the range of human hearing...

[@Jujudo]

possumverde I guess you'd just put a skype call on your phone to a laptop at the open end

[@Fearjames]

+Yaldabaoth don't you think you could do this with pipe? I'd imagine you fix a lot of tubes together

[@BrendenWasHere24]

I cannot tell you how much I love your videos , I want to be a chemist one day.

[@CheshireTomcat68]

Barking Dog collaboration with The Slow Mo Guys PLEASE!

[@ColtonBlumhagen]

"The Professor will film the experiment on his iPad."

[@tybo09]

The geometry of the tube would make uniform mixing difficult. Is there a way to mix outside of the tube then pump the mixture into the tube?

[@RaExpIn]

I really like the barking dog and the slow motion video is awesome!

[@alejandroghysbrecht6428]

Periodic Videos you are the best

[@Dingomush]

My thought on mixing would be to put a golf ball or foosball in the tube and let it track back and forth to mix. Love the vids. Hats off to anyone who works in the chemistry field, what would the world do without you!

[@ionlymadethistoleavecoment1723]

Neil is the best. But I wonder, why is he always stuck with the cleanup?

[@hypersapien]

Ionlymadethistoleavecoments Yeah, he's like the unsung hero. Ballads should be written about him.

[@darcgibson5099]

Ionlymadethistoleavecoments Because he's a lab technician, it's what they do. Set it up, clean it up.

[@hypersapien]

A ballad is a form of verse, often a narrative set to music. Ballads derive from the medieval French chanson balladée or ballade, which were originally "dancing songs". I stand by my statement.

[@acaryadasa]

That's why they pay him the big bucks.

[@koenth2359]

5:16 Always knew Neil's a ghost

[@user-wg7ut8vn3j]

einstein been real quiet since this video dropped

[@FrottyZaoldyeck]

I like the way the Prof says "tube" :^)

[@markbell9742]

Hi Professor: First thought: since the length of the tube affects the tone maybe the shape would affect the timbre. So, instead of a simple cylinder, maybe flare the end like a trumpet. Second thought: make a sequences of tubes of different lengths stacked together so the first lights the second and the second the third, and so on to play a tune. Third thought: what would happen if you ignite the mixture from the *BOTTOM* of the tube. Cheers, Mark

[@RoastCDuck]

Melting sausages, radiactive ballons, dizzy crystals, there still a tons of awesome flamable stuff to do, i would make a neil meme right now

[@madLphnt]

first one sounded incredible at the end.

[@Mournforthelost96]

I pretty sure this is my new favorite science experiment. Strike that, this is my favorite science experiment.

[@pennernderpenner]

Hey! I would suggest to put a chain inside the tube to accelerate the reaction, by causing small turbulences.

[@KOZMOuvBORG]

It's normal with organ pipe construction that the diameter goes up in some ratio to the length, perhaps using a wider tube for such would improve the tone of the 'bark'. Could envision someone setting up enough pipes to play a few bars. Beethoven 5 or O Canada to start?

[@emrad9595]

Oh, I think I just realized where I've seen that kind of flame reaction before! Specifically, the bouncing pressure wave in the tube! What I think you've got going on there is basically the makings of a valveless pulse jet... without the continuous feed of fuel and O2... Emrad

[@pbj4184]

Could you please explain the mechanism?

[@richarddenton3390]

"The professor will be filming on his ipad"

[@taralovescm]

Please come to Blackpool Sixth 2017!!!! It would make me ridiculously inspired, always wanted to get the chance to hear you talk Professor :)

[@GrafKrolock82]

The first attempt (01:57) really sounds like a big barking and growling dog... Is there a maximum speed of that flame? Given that there is a very long tube (some 10m+) containing the ideal mixture. Will the flame's speed be limited or will it reach speeds, where a shock wave shatters the glass?

[@thebestofall007]

This one sounded not only like a barking dog, but also like a growling dog in the end of the tube.

[@therealhellkitty5388]

I want to see the bottle brush you use to clean that tube...must be a beast.

[@beachboardfan9544]

How about the 10ft barking dog experiment but horizontal and lighting it from both ends simultaneously? How would the wave propagate? Constructive or destructive interference?

[@T3sl4]

I think the nonuniformity is due to reaction speed (which is nonuniform), which tends to eject a lot of the sulfur up higher, and leave finer deposits in the bottom end (by the looks of it). As for the reaction rate, the problem with a long, thin tube is the attenuation due to viscosity in the tube, and perhaps, acoustic dispersion making pulses less easily resonant. I think this is why the reaction takes time to begin oscillating: the feedback gain simply isn't very high, so it takes some time (and distance) to begin oscillating. Something similar probably happens at the bottom, where so little reaction is taking place relative to the huge column of air above it (now also much hotter, and so, having a higher speed of sound), that it doesn't oscillate. The oscillation could also be quenched due to the interaction of the 1/4, 1/2 or 3/4 wave distance from the open end, and 1/4 wave (at some frequency) distance from the bottom end: in other words, the position it stops at might be characteristic, if not geometrically so (because of the difference in speeds of sound). Lots of interesting phenomena going on, a rich bit of physics and chemistry!

[@trespire]

Tim Williams Thanks for the insight :-)

[@apburner1]

Any idea what kind of pressures are developed in these tubes? Is there ever any possibility of the tube overpressurizing and bursting?

[@TheFlacker99]

What if you do this reaction in a klein bottle?

[@Reptiliancentaur781]

TheFlacker99 (Flak) you'll have a bomb

[@hotdrippyglass]

The inner geek within me wonders if opening both ends will change the acoustics because the end cap reflects the pressure front back into the flame transition point. Nice work.

[@priitmolder6475]

"Gentelmen, BEHOLD. I have made...a 10 foot barking dog!"

[@kingcellaa]

Amazing video

[@daily8150]

The fluorescence was amazing.

[@TeemarkConvair]

would not the shock wave be causing the mixture to re-distribute the gasses? is it possible to determine whats causing the different pitched sounds? the raspy higher pitched portion may indicate much more rapid, localized, pulses? very interesting to say the least, thanks

[@LiquidZulu]

5:04 well then...

[@mycommentcamefirst1910]

I didn't think anyone had noticed that XD

[@CSWSNomadFTW]

I just did, i was checking the comments to see if anyone beat me XD

[@VicodinElmo]

We all noticed it. Don't pretend you didn't hahaha.

[@mojosbigsticks]

I never knew the shape and volume of the vessel could make such a difference to a chemical reaction. A very interesting side effect.

[@ChrisThomasBone]

What if the tube was wider as well as longer? Or perhaps instead of being longer? What if the width wasn't constant along the length? What if the tube branched off?

[@Snoogis]

I love this experiment

[@nayrleinadcm]

In the previous Horizontal Barking Dog video, the Professor mentioned something about the flames acceleration possibly being caused by the air getting compressed as the flame moves toward the bottom of the tube, might the slower start in this experiment be due to the fact that in a large tube there is more air (and tube) below the flame that needs compressed?

[@shapshooter7769]

Maybe the rate at which the reaction progresses is correlated to the harmonics of the tube? Have you considered that? I personally can't do my experiment to prove that but the flame looked like it slowed down at a node.

[@CynicalScientist261]

I wish the professor had more time to make videos. I’ve already watched them all 😅

[@frankd7339]

Thank You Neil :)

[@JohnMichaelson]

So if you do this in a standard small test tube does it turn into the Yapping Chihuahua?

[@logtothebase2]

Would make a good message tone for a mobile phone!

[@chrisspence6484]

Hi professor First I would like to say I love your videos. I have a query about the barking dog that you may like to investigate. In your video you said it was probably a pressure wave causing the flame front to oscillate. I think it may actually be glugging like pouring milk. Thoughts please.

[@papanyanz]

You have done it also in horizontal tube, but what if you lit it from the reverse side - from the bottom next time?

[@lancejobs]

Very lovely blue, reminds me of, Cherenkov radiation, you guys should talk about that one sometime.

[@anoopsahal1202]

How did you tune the glass cylinder to give that heavenly synthesiser type sound in the slo mo ?

[@Nighthawke70]

You can see rings of flame emanating from the top of the flame column as the reaction progresses, suggesting the shockwaves are disrupting the column. This may help in understanding why the barking dog moves the way it does.

[@IamGrimalkin]

GaryKildall Quantum mechanics is not just restricted to quarks. Chemistry is about atomic orbitals, which come from quantum mechanics. Also, chemistry doesn't really consider protons and neutrons either, just nuclei.

[@MortRotu]

Does a strongly oxidising solution dissolve the Sx chains? thinking something like an acid piranha would oxidise the S to SO4 and make it easier to remove. Don't use aqua regia.

[@davidhague2840]

Fascinating!

[@Taras195]

YAAAY! New video!

[@acaryadasa]

I haven't watched all of the barking tube videos in a row so maybe it is addressed in other videos. But does anyone know or have a guess why the flame advances down the tube in a pulsating manner, rather than at a more regular pace?

[@acaryadasa]

Ooops. I see that it was discussed in the Barking Dog (slow motion) video.

[@richardtickler8555]

could you make that in a even bigger tube (e.g. industrial chimney and mix it by trowing stuff down the chimney)?

[@richardtickler8555]

like fanblades that are spinned up at the top an them let go

[@mincemeat1016]

Nilered brought me to this. Finally I found it

[@PunTimesWithNeil]

Me too

[@otonanoC]

cranking the volume on my headphones

[@GearsNCarpentry]

Is the oscillation of the flame from the nitrogen gas being released?

[@TheChipmunk2008]

"Neil, if you can just scrub that out, there's a good chap"

[@flaplaya]

I wonder the correct stoichiometric ratio between CS2 and N2O is. Anyone know?

[@MichelKiflen]

What's the song towards the end? Like a chime or something..?

[@JayMark2049]

Still like the way the first one went. It kinda ''barked'' in the middle and then made that nice ''tube sound'' at the end.

[@flaplaya]

Wow, is that a barking dog record? And holy jeez is Sulfur a complex and very cool element. Metallic and even superconducting properties with the S-II, S-III, S-IV, S-V phases (Allotropes of Sulfur - Wikipedia) Unbelievably interesting :)

[@kasnitch]

taken out of context , it's almost like a 3m yellow light saber turning on. briefly. would the mixing go better if all the ingredients were added into a hand pressurized yard chemical sprayer, then into the glass tube in a mist ?

[@abyssaljam441]

Would you be abel to have a wider tube? Like a large bulb.

[@vatossan]

what if you contain the barking for a long time. is it possible?

[@isupermandude]

5:04 Hmmmmmm

[@jdgrahamo]

I would have thought that in a tube that long, any water would tend to simply run along the side of the glass without overly affecting the gases. Perhaps some sort of perforated piston, like the disc in a cafetiere?

[@ApertureWarrior]

It would be interesting to see what would happen if you Did it horisontaly and lit it from both ends simultaneously especially with the bouncing... Not sure if the glass would take the strain or if it would explode but it could be cool

[@walterdennisclark]

The fourth of July fireworks called "the screamer" works the same way. I suspect.