A wonder how any of us lived long enough to reminisce

Off-topic conversations and chit-chat.

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A recent post by Peter made laugh out aloud

He then violated SOP A 1 Engage Brain Before Any Action and held the beaker above the FID, leading to rapid implementation of procedure OSHIT 3 applicable in cases of small quantities of flaming liquids held by hand in glass containers.
Sometimes I wonder how any of us lived long enough to be reminiscing on Chromforum.

It set me thinking.

From experience - in chronological order

Boiling benzene in an open beaker over a Bunsen burner in the school lab.

Slightly before my time but seeing photos of the oven door of a GC blown off and embedding itself into the wall after a hydrogen leak in the oven. Later GCs had a spring loaded inner door to relieve the pressure.

In the early days of LC, after gradient elution, the only way to tell if the starting solvent conditions had been re-established was to hold your finger under the eluent and sniff. Hexane could really make your head spin and MeOH/CHCl3 would really sting an open cut- even worse if accidentally spilt onto your lap:-)

Modifying a Pye moving wire LC detector. This was the closest to a "universal " detector. Essentially the eluent dripped onto a fine wire that moved between two spools. The wire went through a heated chamber and the sample evaporated off into an FID

http://www.chromatography-online.org/Tr ... s_5_64.php

My "clever" modification of adding an air jet to change the drips into a spray onto the wire to coat the wire more evenly to improve the detection level worked brilliantly - for about 60 seconds. After which the vapour ignited and set fire to the instrument.

Whilst rinsing out my syringe with Tri-sil BSA in pyridine for a manual injection I accidentally injected my left thumb with 10uL - there was a numb spot for many years afterwards.

From the actuarial tables chemists seem to come off lightly.

I once pressed "ignite" on a flame photometric detector that had one of those 100 ml bubble flow meters connected to its outlet. The mixture of hydrogen and air in the connecting pipe and glass tube went off with an impressive crack and a jet of flame shot out of the top of the meter - but everything held together.

Peter Apps
My best memory from high school chemistry class: The vice principal was subbing for our chemistry professor. He decided to do a demonstration for us to show just how reactive sodium is in water. I'm glad he at least used a blast shield! The resulting explosion burned through the ceiling and dislodged most of the ceiling tiles in the room that it didn't burn. The entire building was evacuated as the fire alarms were set off and the local fire department was called in. We made the local news that evening. I've been a great fan of the sciences ever since.
When I was planning on being a teacher, during my student teaching the co-op teacher had me pour about 25mL of waste acetone into the sink. I think his thought was that it would evaporate just fine. In the first class he had me showing off a Tesla coil and specifically had me show that it could ignite a paper towel. Rather than continue to hold a burning piece of paper as it reached my arm I dropped it into the sink. There was a nice 'woompf' as the acetone that we had forgotten about released its energy.

That woke me up and got the students to all pay attention to my every word that day.
I was a teaching assistant in Organic II lab in college. In the pre-lab lecture the professor mentioned at least four times that when you get to the point of heating the ethanol used in the recrystallization to use the electric heating mantle. Well as the lab progressed I see a student setting up a ring stand, ceramic square and Bunsen burner. I asked him what he was doing and his reply was "I'm getting ready to heat my ethanol." I simply walked over to my stool and sat down to watch.

A moment later he sat the beaker of ethanol on the stand and lit the burner. About the time the ethanol began to boil there was a soft "pooff" sound and a nice blue flame about a foot high appeared above the beaker. He looked at me with the most shocked expression on his face and I said "Now what are you going to do?"

I just walked over and placed a larger beaker over the burning one after turning off the gas to the burner. About that time I looked around the lab and saw the other ten students slowly putting away their Bunsen burners. At least he wasn't the only one not paying attention in the pre-lab, seems every single student was day dreaming during the safety part of the lecture.

Never be the first one finished, let someone else make the mistakes so you don't have to :)
The past is there to guide us into the future, not to dwell in.
A similar story:
In college I was a lab instructor for an intro chemistry class. There was one particular lab that required the use of a dry ice/isopropanol bath to cool something or other. That particular lab room had heavy stone (non-flammable is the important part here) lab benches.

So after everyone has finished up and is quietly writing up the last part of their lab reports, I take a portion of alcohol from the dry ice bath, and walk from one end of the empty bench at the front of the room to the other, discreetly pouring a continuous "puddle" of alcohol along the bench as I go. When I reached the end of the bench, I pulled a lighter out of my pocket and lit one end of the "puddle", resulting in about a 1-2 foot high line of flames that traveled from one end of the bench to the other. I have to say, it was pretty impressive. The students who weren't scared thought so as well.

Luckily none of the students in the lab mentioned that particular "demonstration" to the professor.
My own student teaching experience -

My demo involved making acetylene from water and Calcium Carbide... in a balloon.

Said balloon self inflated nicely after I added the reactants and tied it off. Next step was to tie the balloon to the end of a yardstick securely mounted to a bench top and burst the balloon with a flaming match mounted to the end of another yard stick.

Instead of having a nice little fireball, the match produced a nearly microscopic hole right where it was knotted and fastened to the yard stick. I produced a jet that did two large, level circles around the room before making a bee-line for the curtains.

Fortunately, it ran out of fuel as it reached the curtains.

I followed up the next week with a little batch of NI3.
Did you know that if detonated before drying is complete, that stuff will stick to, dry out, then detonate on every nearby surface leaving lovely purple stains?

I'm far more dangerous in a classroom than in a lab. Be glad I chose labs in the long run.
I'm far more dangerous in a classroom than in a lab. Be glad I chose labs in the long run.
You're not the only one! :lol:

Fresh out of college, my first job was teaching high school chemistry & math (at the same high school from which I had graduated four years earlier). Like you, demonstrating exothermic reactions, but by putting a coffee can over the carbide + water. The coffee can had a nail-hole punched near the open end to which I could touch a lighted taper. The trick was to count to ten before lighting off in order to allow for a good mixture of acetylene + air. Result was a mildly satisfying pop as the can jumped up a couple of feet.

Then I got the bright idea of running some O2 from the glassblowing torch into the inverted can before putting over the carbide. I got a bang sufficient to blow the can up to the ceiling of the lecture room (12 feet), leaving a visible dent in the plaster and accordioning the top of the can by a good centimeter on one side. Fortunately, no one was hit by the ricocheting can.
-- Tom Jupille
LC Resources / Separation Science Associates
+ 1 (925) 297-5374
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