How cold?

[dizzyblonde]

I think what concerns me is, the education vystem must be churning out some really thick numpties.
Do they not teach chemistry, physics and biology anymore?

Oh....I forgot, in my day they dropped such things for general science, so playing with liquid nitrogen is the stuff read in story books! If kids were educated properly, they wouldn't be up for a laugh in a pub with it.


Heston blooming heck has a lot to answer for too.

I have had a discussion about this earlier today with one of the Chemists on my site.

Also being of a chemistry background by education and trade I can see what they were attempting to do.

The effect seems to have been to try and get the effect of "dry ice" which as most people will know is frozen Carbon Dioxide. Now, either someone though "oh no, we can't give them carbon dioxide, they'll asphyxiate! I know, we'll use Liquid Nitrogen as Nitrogen is about 78% of the composition of 'air'," or liquid Nitrogen is cheaper.

But, "dry ice" is about -78.5'c, where as, as pointed out, liquid Nitrogen is used at about -196'c, so, basically someone didn't engage the "common sense" part of the brain before thinking this was a good idea

Originally Posted by JamesMio

At the risk of getting all deep here, what's more concerning (to me at least), is that the people who are stupid enough to do this, had the money to do it.

i.e. despite being so utterly brainless, they have a disposable income. Thus, either somebody actually employs them, or (as I suspect may be the case), they're in receipt of some form of hand-out, in which case my taxes are paying for retards (like this) to do stupid things (like that).

Is there a 'stop' button anywhere, because I think I'd like to get off now please.

Fully agree, these people should never be allowed to operate machinery, drive a vehicle etc, there is no hope.

I found a recipe for a liquid nitrogen cocktail http://chef-a-gogo.com/tag/liquid-nitrogen-cocktail/
The ingredient list is:
Liquid nitrogen martini ingredients


5 ml lychee liqueur (Use Suntory Mango liqueur if available)
50ml Absolut Mango vodka
30g very ripe mango cubes (in season)
25ml liquid nitrogen
20ml pineapple juice, freshly squeezed
5ml lime juice, freshly squeezed

The guys website is clearly that of a foodie, or atleast someone who likes different drinks. But the entire lack of understanding of this stuff is worrying. Yes it is a very good way to cool the drink down without changing the composition, but he also says to serve it quickly whilst it is still "smoking". er, excuse me?! That means that it has not all evaporated. (I got my units wrong earlier. 25ml of liquid nitrogen is just under 24l when vaoprised, done the calcs more accurately this time.)

[yorkie_chris]

If there was that much N2 in it surely the drink would just be a solid block? If that is 25ml poured into a glass how much vaporises on the way into it?

This is the problem with the youth drinking these poofter drinks. Being female she should have been served a small white wine.

Originally Posted by ClunkintheUK

Still think the bar should be shut down for such a stupid idea, but then does anyone remember those oxygen bars, where you could breathe pure oxygen (which is toxic in all but very small doses).

No it isn't...

It becomes toxic at high partial pressures... like breathing diving gasses deeper than intended. At surface pressure it can be breathed for many many hours before (fairly benign) pulmonary oxygen toxicity becomes a problem.

... as we all know: Your average British 18 year old on their birthday is completely sober and lucid enough to know:
1) What's in the drink his/her mates have just bought for them and are all shouting in unison "In One! In One! In One!"
and
2) Be able to recall the physical properties of liquid nitrogen when just standing up is creating a serious challenge.

This bar had better have *very* good liability insurance!

C

Originally Posted by Berlin

... as we all know: Your average British 18 year old on their birthday is completely sober and lucid enough to know:
1) What's in the drink his/her mates have just bought for them and are all shouting in unison "In One! In One! In One!"
and
2) Be able to recall the physical properties of liquid nitrogen when just standing up is creating a serious challenge.

This bar had better have *very* good liability insurance!

C

+1

The use of it isn't stupid...
Using a few drops in a drink in pretty harmless (Ref: http://chemistry.about.com/od/advanc...d-Nitrogen.htm)

The lack of understanding by the person selling the drink to educate the person about to drink the drink is the issue (Ref about past dangers of use of it: http://chemistry.about.com/b/2011/04...gen-safety.htm)

In short, the bartender has made a f**k-up good and royally, by either:
- Using too much
- Not informing the girl to wait a few minutes until the mist has gone before she drinks it.
(there is also a third option whereby the bartender did number 2, and it was ignored... wbut who knows...)

Originally Posted by yorkie_chris

If there was that much N2 in it surely the drink would just be a solid block? If that is 25ml poured into a glass how much vaporises on the way into it?

This is the problem with the youth drinking these poofter drinks. Being female she should have been served a small white wine.



No it isn't...

It becomes toxic at high partial pressures... like breathing diving gasses deeper than intended. At surface pressure it can be breathed for many many hours before (fairly benign) pulmonary oxygen toxicity becomes a problem.

A lot vapourises on the way into the glass. I have seen a fairly sizeable (maybe a 1/2 litre) dewer of LN2 thrown across a (very well ventilated) lab floor. It didn't take very long to evaporate, Less than a minute if I remember correctly. I have heard (first hand, i.e. from the persons who saw it) of a small amount of liquid oxygen being thrown over a crowd and evaporating before it reached anybody, but did not see this myself.

Interesting effect of this is that you can put your hand into liquid nitrogen for a short period, about 1-2 seconds. It evaporates in a sleeve around your hand, which acts as an insulator around your hand, just make sure you are not wearing any metal on your hand, it acts as a conductor. It also makes pencil erasers (the big ones, not the ones on the end of a pencil) shatter catastrophically.

Sorry my bad, got confused in there somewhere. Just remember there being a spate of people going a bit funny in those oxygen bars, and from my biology lessons that pure oxygen isn't something to be encouraged, unless you know what you are doing.

Originally Posted by Steve_God

The use of it isn't stupid...
Using a few drops in a drink in pretty harmless (Ref: http://chemistry.about.com/od/advanc...d-Nitrogen.htm)

The lack of understanding by the person selling the drink to educate the person about to drink the drink is the issue (Ref about past dangers of use of it: http://chemistry.about.com/b/2011/04...gen-safety.htm)

In short, the bartender has made a f**k-up good and royally, by either:
- Using too much
- Not informing the girl to wait a few minutes until the mist has gone before she drinks it.
(there is also a third option whereby the bartender did number 2, and it was ignored... wbut who knows...)

All the reasons here why it isn't a stupid idea revolve around all involved knowing what they doing/what is involved. If your drink it while its still evaporating will give you a pretty good case of gas at best.

Yes, used properly i can see its very useful in the culinary industry, but in a bar in a town centre on a saturday night... that was always going to end in tears eventually. I would not be surprised that some bars did it, hoping they were not the ones caught out.