Smelly Chemistry - Periodic Table of Videos

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11 жыл бұрын

Mercaptans - or Thiols - are some of the smelliest chemicals around. We didn't dare open the bottle.
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From the School of Chemistry at The University of Nottingham: www.nottingham.ac.uk/chemistry...
Periodic Videos films are by video journalist Brady Haran: www.bradyharan.com/
Brady's other channels include:
/ psyfile (Psychology stuff)
/ sixtysymbols (Physics and astronomy)
/ numberphile (Numbers and maths)
/ deepskyvideos (Space stuff)
/ nottinghamscience (Science and behind the scenes)
/ foodskey (Food science)
/ backstagescience (Big science facilities)
/ favscientist (Favourite scientists)
/ bibledex (Academic look at the Bible)
/ wordsoftheworld (Modern language and culture)
/ philosophyfile (Philosophy stuff)

Пікірлер: 386

@br0sRchill 11 жыл бұрын

0:37 "le stink"

@karmakazi219 11 жыл бұрын

On a "normal day" there are 8000 gas leak reports?!?!

@AntiProtonBoy 11 жыл бұрын

I'd love to get my hands on a Tellurium based stink bomb.

@andreibusuable 10 жыл бұрын

You guys make chemistry so interesting.

@fackingpos 9 жыл бұрын

Fart in your general direction!!!!

@Obsidus 11 жыл бұрын

Prof. Poliakoff is amazing.

@MichelDellaCompta 10 жыл бұрын

I live in the city where the mercaptan leak happened, it was pretty bad..

@TheChemiKid 10 жыл бұрын

Anyone hear breaking glass @ 3:53?

@jbrowsingj 11 жыл бұрын

Fantastic work again, Brady! I'm subscribed to all of your channels, and really excited to see where you'll take them. I really appreciate how non-technical you keep them, but could you post links or a full title of any papers that are discussed in the videos? Thanks!

@Mivalys 11 жыл бұрын

"...to see how her hair compares to mine." I loved that argument. :)

@mixolydian2010 10 жыл бұрын

Brilliant love all these videos..it is my current favourite channel. Thank you all very much for your work on these productions and especially to the prof for his humble and clear explanations of the chemistry involved.

@pecfree 11 жыл бұрын

WE LOVE YOU PROFESSOR! KEEP THE VIDEOS COMING GUYS!

@RokitScientist1987 11 жыл бұрын

Awesome content. I'm astonished by the amount of detail and the amount of interesting and useful information shared.

@pmarceau 11 жыл бұрын

I find it interesting that a dog's sense of smell is so much more sensitive than ours, yet bad odors seem to bother them much less, if at all.

@adfkjgvdjfvbdbvdkjvb 11 жыл бұрын

the line "I fart in your general direction" springs to mind... ;)

@SrikarManepalli 9 жыл бұрын

Nice tie Professor

@PINGPONGROCKSBRAH 10 жыл бұрын

"Professor Moody" lol did anyone else think of Harry Potter?

@_starter 10 жыл бұрын

And then it would be a bit late.

@SnowRaptor 11 жыл бұрын

A few years ago, a truck carrying mercaptans tumbler over in São Paulo, triggering lots of phone calls to the firemen and to the gas company even from the other side of the city. One biker asked me in the car what happened and it took me some time to explain to him.

@HolyBookProductions 11 жыл бұрын

One of the best Chanels on KZfaq

@djmussy18 11 жыл бұрын

Thank you for this wonderful video.

@DevilMaster 11 жыл бұрын

Reason #1 is that the smell of grapefruit is not ONLY due to thiols. Reason #2 is that a substance can be perceived as having a different smell dipending on its concentration: for example indole, which smells like flowers at low concentrations, while it smells like shit (literally) at high concentrations.

@pwhiteOO 11 жыл бұрын

excellent episode. thanks

@vgoj 11 жыл бұрын

superb as usual. Got ot love Prof. Poliakoff.

@PKFreezeBETA 11 жыл бұрын

It doesn't really do anything chemical, it just fools your nose into not smelling the skunk spray as much. basically, what happens is your nose gets used to smelling the skunk smell, and after a while it stops smelling quite as strong, and the tomato juices more pleasant odour is enough to mask the skunk smell. to anyone who hasn't been around the smell for very long, it still smells awful. the process is called olfactory fatigue.

@heyandy889 11 жыл бұрын

brady haran is like the johnny appleseed of KZfaq spreading knowledge far and wide

@callumwatson7582 11 жыл бұрын

I love these videos

@sazarod 11 жыл бұрын

Major points for plugging the vibration theory of olfaction!

@bojor7 11 жыл бұрын

i always love to see a gorgeous Schlenk Line!!!, keep bringing Organometallic Chemistry

@dflxxhunterxx2 11 жыл бұрын

Hey periodic Videos! I happen to work in an oil refinery in Germany, where we actually remove naturally occurring Mercaptans from Propane and Butane using NaOH to bind them and then oxidize them with air (and some catalytic wizardry ;-) )

@MichaelZola 11 жыл бұрын

thank you for the new channel recommendation

@mauroprovatos 11 жыл бұрын

I was expecting Brady to have a sniff test.

@Nikolaii2571 11 жыл бұрын

Mercaptans are also used to synthesize a sedative-hypnotic called "SULFONAL" and "TRIONAL" which were widely in use a century ago.. Sulfonal was a condensation reaction of Ethyl mercaptan and Acetone.

@CaptTerrific 11 жыл бұрын

Any chance we could see a followup to the sodium/water video, where you make better use of that amazing phantom camera? Thunderfoot made some very interesting observations about your theories, and the potential for the Periodic Videos to actually contribute to a new scientific discovery, instead of simply giving demos, would be amazing!

@qwaqwa1960 11 жыл бұрын

I've attended a *couple* of lectures that talked about the apparent quantum effects in smell (and other biological processes)!

@TheWildHaggis 11 жыл бұрын

This video reeks of great stories!

@dodgevipr44 10 жыл бұрын

I've heard that the texture on the surface of the mentos permits the carbonation of the drink somewhere to attach, and it makes the soda fizz up.

@urost032 11 жыл бұрын

Good question. The most amazing fact about some thiols is that you can actually smell some of them in very highly diluted forms, and when in low concentrations they tend to smell quite nice(just to give you the perspective of how diluted they have to be in order to smell good(this is not in general): 1 mg of thiol per 10000000 dm3 of H2O! Amazing, ha!) Also, grapefruit contains some other compunds which give smell to it(mostly esters).

@KoenigNord 11 жыл бұрын

I used thiols for a long time, since they bind on elemental gold very well. with this, you can create amazingly useful functional surfaces. Luckily my thiols were to big to smell :)

@BeastOfTraal 11 жыл бұрын

You should do a video on chirality (left handed vs right handed molecules)

@Jnashalt 10 жыл бұрын

An introduction to an eduational kit employing the sense of smell for teaching chemistry developed by Simon Rees, Rebecca Edwards, and Jacob Cox through the Royal Society of Chemistry, Educational Techniques Group and Durham University.

@MasterFPunkt 11 жыл бұрын

A new science channel ?? Great Scott !

@Nexus2Eden 11 жыл бұрын

How funny you should do this video now. I was just talking with a friend about how Skunk smell (from a dead Skunk - road kill). I was commenting on how the odor, like Camphor, sticks like glue and lasts so long. I postulated it was because they are aromatic rings, and quite stable. So the phenol compound would persist and must be highly reactive. ...and here is video on it, brilliant! :D

@tybo09 11 жыл бұрын

Sorry for another question: Is the mercaptan's mercury capturing ability related to the sulfur atom? I ask because we have mercury spill kits in our equipment shop and they all contain powdered sulfur.

@TheWanderingChemist 11 жыл бұрын

You forgot about furfurylthiol! The coffee smell! :D

@xnax1993 11 жыл бұрын

God, I love the professor!

@ltericdavis2237 11 жыл бұрын

If your confused, numberphile (a show made by the same guy who produces these videos, in case you don't know), made a video explaining that. KZfaq's counting system stops at around 300, so it can add advertisements, if I remember that correctly.

@Jotto999 11 жыл бұрын

I've read the series throughout, grew up on it. I was thinking how it'd be during the series, I probably because I've been reading HP:MOR lately.

@ltericdavis2237 11 жыл бұрын

Thank you for explaining. It has been a while since I saw the vid. It appears I forgot some details.

@khajiit92 11 жыл бұрын

elements heavier than iron come from that explosion you just mentioned. our sun is a second generation star, the heavier elements in our solar system come from an older star that exploded.

@KennyTheB 11 жыл бұрын

I can't speak explicitly for that particular compound, but generally, compounds that utilize heavier elements in this manner tend to become pretty toxic pretty quickly.

@killzonia 11 жыл бұрын

They're talking about optical isomerism, or chirality, which involves molecules that are non-superimposable mirror images of one another (put one of your hands on top of the other; they are the same shape but are non-superimposable). They are identical in most ways apart from a few, such as how they rotate plane polarised light or, more relevantly, how they interact with biological receptors, i.e. how they smell, taste, etc.

@boboblaw 11 жыл бұрын

BRADY!!! why must you make more channels for me to subscribe to????? i already have 188!!!!.......189 now guh, damn you and your ability to know exactly what i want to watch.

@hunnis12 11 жыл бұрын

Prof. Moody and Prof. Moriaty? You're the best..

@rcdude29 11 жыл бұрын

YAAAAAAY! New Video of periodicvideos :))))))

@Bsgetsreal 11 жыл бұрын

Your tie is awesome!

@Premoose2 11 жыл бұрын

Hey Brady, just wondering if you guys are going to respond to Thunderf00t's newest video? Anyways, great videos like always.

@WolfDOuka 11 жыл бұрын

I think you should do a video on the chemicals in the brain and what their function is. One interesting video could be also what if the chemicals in the human body are not balanced. :)

@Gibbsbc1 11 жыл бұрын

That is some quite good evolutionary psychology.

@splitinfinitives 11 жыл бұрын

I already knew about psyfile bit when I heard him say new channel I just thought 'really Brady? ANOTHER CHANNEl?'

@Versudan 11 жыл бұрын

I'd like to see that paper about Deuterium vs Hydrogen smells Professor. I mean, Deuterium is a different atom from Hydrogen, even if it uses Hydrogen as a base. Could you possibly provide us a link to an online copy of the paper or something? I might need to read it a bit before I can accept what it says, because on the surface the paper doesn't sound like the experiment was properly thought out.

@ThinkingSpeck 11 жыл бұрын

As I understand it, we evolved that revulsion because spoiled food tends to contain thiols. It's not that the thiols themselves are toxic in those quantities - it's just that they're very easy to detect and they tended to be associated with other chemicals which were dangerous to us.

@adavewiley 11 жыл бұрын

My high school biology teacher wanted to teach us why asparagus pee smelled the way it did. He opened a bottle of methyl mercaptan in the fume hood without noting the boiling point. It boiled away immediately, went up the fume hood, across the roof, and back down in the windows. We had to stand outside for a few hours, but I never forgot asparagus's secret ingredient.

@nagromgreen 11 жыл бұрын

So are mercaptans part of the compound beta-mercaptoethanol? We used that in intro BCEM but alas I am not a chemist.

@rasanjadampriya 11 жыл бұрын

Do a video about superconductor metals and how they work

@therobotFrom94 11 жыл бұрын

Do the Selenium/Tellurium compounds have similar, but worse, smells to thiols? or are they different and worse

@awimachinegun 11 жыл бұрын

he has some good criticisms and additions.

@justrockthisworld 11 жыл бұрын

i smelt it :( a lot of the alarms in the city went crazy :)) i'm happy that now i know exactly what it was. thank you! :)

@PatoPatoEloElo 11 жыл бұрын

Glad to the that professor was on a good mood

@KialraOfDeath 11 жыл бұрын

Strawman argument, beautiful.

@MakuziTheInuk 11 жыл бұрын

if he was my science teacher i would love science again

@JonesAndGriesmann 11 жыл бұрын

I have a question for you. When the Snow melts where does the White go?

@jmrdelorean 11 жыл бұрын

being a chemist the worst thiol I had to deal with was the diester of thiol succinic acid. You had the wonderful sweet smell of the ester with the rottenness of the thiol. It was awful. If even a trace was spilled you'd smell it for weeks.

@ammelr 11 жыл бұрын

A few months ago, the Japanese isolated a compound that smells like vanilla from cow manure. Indol is commonly used in perfume, but also contributes to making poop stink. A little thiol makes garlic and grapefruit smell good, a lot smells like rotten eggs. Chemistry is very strange.

@krazyking424 11 жыл бұрын

Is it possible that there is a mechanism in the nose to isolate the sulphur-hydrogen bond from the triols? Then we would just be recognizing that bonded pair. I guess the issue would be if that bod was stable and how much energy would go into isolating it (also if that is actually how it's done)...

@glenwoofit 11 жыл бұрын

The idea of comparing hair with the proff did it for me! I'm off to "Go Compare, Go Compare"

@heyandy889 11 жыл бұрын

the professor did say something about that. apparently natural gas/methane has no smell, so something, like one of these thiols, is added in order to let people detect the gas.

@melekhthechanger88 11 жыл бұрын

I have made grapefuirt mercaptan before from pulegone and H2S :) it really really smells bad as I had to make 17grams of it!

@akkudakkupl 11 жыл бұрын

Probably the same way we make heavy atoms - colisions. Also its not just - out of H start fusing He, out of He start to fuse Li. Because then we would end up with mostly even atomic numbered elements.

@TheGhostbuster1989 11 жыл бұрын

sometimes, where the chemical is faceing is very important, especially when dealing with drugs. look for some thing called enantiomers (if i try to explain it, it would take me days)

@ExtrasAreOrdinary 11 жыл бұрын

Usually "R" denotes a hydrogen or a hydrocarbon side chain (of some length).

@inventorOz84 11 жыл бұрын

what about Betamercaptoethanol which we use as a reducing agents in the biochem?

@en4rab 11 жыл бұрын

There is a talk from TED.com on youtube here: watch?v=yzOcvINn8Iw in which Luca Turin talks about why he believes we smell vibrational frequency's and a possible mechanism for it and how he founded a company making scents for the perfume industry based on this. I found it quite compelling.

@bullar400 11 жыл бұрын

At 8:38 It is written (RSH + 3NaOCl). What does the "R" mean?

@NekysAcherontios 11 жыл бұрын

i still remember one of my profs saying that two moles os "shitol" make jasmin

@OSPeters 11 жыл бұрын

I love this guy, and his tie... I want his tie.

@OnceUponATimmyy 11 жыл бұрын

What is a left or right handed molecule? and what is the difference?

@007bistromath 11 жыл бұрын

I had a thought while watching this video about why these chemicals might all smell so bad. It occurred to me that the characteristic carbon-sulfur-hydrogen group was like a hook, and the various mercaptans would be different things hanging off that hook. Perhaps our sense of smell works analogous to a scale, "weighing" whatever's on that hook. This would explain why the selenium and tellurium analogs are worse, as well.

@NinjaXM0 10 жыл бұрын

By left handed and right handed molecules does he mean optical isomers ?

@knockdoun 11 жыл бұрын

My Paramedical Biology Teacher once brought Durian fruit to show the class, the moment she took it out of the plastic the pungent smell filled the room and lots of people in the school thought there was a gas leak.

@1999Kimi 11 жыл бұрын

Can you please explain the diet coke and mentos reaction?

@astaiannymph 11 жыл бұрын

I love that the selling point for psyfile is to compare his daughter's hair.

@neverXuploadXvideos 11 жыл бұрын

Can someone explain to me the nomenclature of 2-methyl-2-propanethiol? The compound looks like it ought to be called 2-methyl-2-thiol-propane. or 2,2-dimethyl-ethanethiol

@Syltibob 11 жыл бұрын

Does this mean that you can get rid of the smell from skunks with bleach?

@UnicornStarShip 11 жыл бұрын

When you talk about "left hand" and "right hand" compounds- are you talking about cis and trans isomers? One of the few things I still remember from a university chemistry class 10+ years ago....

@dragonbalism 11 жыл бұрын

I like periodically glancing at his tie.

@danieljryba 11 жыл бұрын

The Prof. Should make a video explaining Right-handed vs. Left-handed molecules.

@Syzygy2048 11 жыл бұрын

Do thiols pose health hazards? The story about the firemen and the building that had to be evacuated kind of made it sound like that.

@ThinkingSpeck 11 жыл бұрын

Martyn, you say you find it very unlikely that thiols' bad smell to humans is due to the vibration - you suggest instead an evolutionary explanation. I agree with your evolutionary explanation as the ultimate cause, but there must also be a proximate cause or mechanism (which I think is probably vibrational frequency). For instance, (most) birds can fly: ultimately because flight was evolutionarily advantageous in the distant past, but proximately because they now have wings and so on.

@nowiecoche 11 жыл бұрын

I wouldn't name "2,2-dimethyl-ethanethiol" b/c the parent chain should be named with the longest number of carbons, which is propane. But the difference between "2-methyl-2-propanethiol" and "2-methyl-2-thiol-propane", I don't know. The thiol and propane belong to two different functional groups so it has to do with that.