Absolutely terrifying moment..
I was never particularly "bad" but I certainly had fun when I was younger in school. It was a great time for me and I got into some bother at times, but nothing major. Until one day in Year 10 English Lit (or just after).

A friend of mine somehow managed to steal Potassium from the Chemistry store room, yet I have no idea how or why! This is the stuff that is kept in oil as it oxidises in the air as it is so reactive. This absolute moron was carrying around a lump the size of an average dice or a cube with the dimensions of a postage stamp, wrapped up in paper. Brilliant.
He decided to show me and my friend in English of his finds when the teacher had left the room. He happily handled it and cut some off (approx 1/2 to 1/3) with a ruler as it's a lovely soft metal and wrapped it in a page of A4 and flung it towards me. I had to do something as the teacher had just walked back in, so I handled it carefully and laid in on the (lino) floor and remember realising it was a little to warm. The other "friend" who I shared a table with had handled it with his hands, and the tiny pieces of metal which had stuck to the sweat on his fingers were sparking and making tiny pockets of smoke appear and was, apparently, painless.

As soon as the bell chimed informing us that it was the last day lesson of the day, I picked up the bit of paper and marched out the door. Like a twat I placed it loosely in my coat pocket and shielded it with my hand and bumped into a friend who had just come out of an adjacent class. I got my head down and asked him to march with me in a serious tone and he obliged knowing something was up. Typically we hit the wall of students all in a frenzy to head out of the the exits and my heart sunk as I felt the warmth of the paper and saw a teacher directly across from me. She was a PE teacher and didn't really know me (as she only taught girls).

It happened in a second. The paper began to burst into flames violently as I instinctively flung it from my pocket into a makeshift firework and watched the reaction get evermore violent and all attention turn on me (obviously). A few shrieks and me stamping like a wild man on it, I look around to see a few dozen students all staring at me and the smokey mass on the floor which I have stamped into oblivion. The teacher obviously came over towards me, and I felt faint. I was pale as a ghost. I was more worried about being blown up as I have seen the capabilities of such a dangerous metal in a controlled experiment the size of a grain of rice and I had a much larger chunk. I was also worried as this was easily an "expellable" situation as well as fire alarms and fines for calling out the Fire Service.

I was terrified and the teacher could see this. HOWEVER, she marched up to me with a quizzical expression and asked plainly "What is going on?!" I wouldn't consider myself a natural liar, but I insisted I saw the piece of paper fall from the stairs from above and it landed on my shoulder and I merely threw it off me and stamped it out. I played up to being scared and burbled "It scared the life out of me! I thought someone had set my bag on fire!". She paused for a second and unbelievably lapped it up! She even asked me if I wanted to see the nurse as I looked pale! I declined gracefully and insisted I could walk it off. Nobody said anything else about it and she had a quick look around by the stairs for any signs of this phantom arsonist.

I almost vomited from the masses of emotions I felt about 5 minutes later on my walk home. And I think the thing that topped it off for me was the fact she saw me the next day and kindly asked me how I was. I smiled and said fine, and explained how it caught me off guard and "shook me up".

Please remember people! I didn't want it! It was thrust upon me and I had to deal with it. And all things considered, I thought I handled it really well!
(Jon_LTD Treat the world like a head!, Sun 11 Sep 2011, 16:25, 6 replies)

Fucking hell. Did anyone pay attention in Chemistry?
There's no way anyone would have sat there with a lump of potassium (and I've NEVER seen one as large as you claim) for more than about 5 minutes before it bursts into flame. A whole English Lit lesson? I think not.

And also, it fucking burns when it reacts with sweat. I have a scar just under my right earlobe to prove the fact. And that was a piece perhaps the size of an iron filing.
( ousgg is not seeking approval, Sun 11 Sep 2011, 17:26, closed)

Perhaps it wasn't Potassium..
But it was something stupidly similar.

A) It was a soft metal which was cut with a ruler
B) It was reacting with my classmate's sweat on his finger tips
C) It combusted with the air (as it was wrapped in paper)
D) It was approx that dimension what I said
E) It was stored away under and students could NEVER handle it

Perhaps it was something less reactive than Potassium, but it happened. It sat in my English Lit lesson for 40 minutes, and obviously some time before that, but for how long I do not know.

I am not lying or exaggerating, but I may have the metal mixed up? The more I think about it, you are probably right. As I mentioned, I'd seen Potassium been put in a water bath which was about the size of a grain of rice and made quite the bang.. A lump my size would have done considerably more damage.

Any ideas what it could have been? There was no bang or noise, just a violent flame spewing out..

This was 10 years ago now.
(Jon_LTD Treat the world like a head!, Sun 11 Sep 2011, 18:12, closed)

Probably
Sodium, it's a little less reactive than Potassium.
( social hand grenade I was a lurker before you were a lurker, Sun 11 Sep 2011, 18:18, closed)

Possibly
You could cut sodium with a metal ruler, probably not a plastic one. And you could conceivably keep a bit out of the oil for half an hour or so if it oxidised neatly. Sodium oxide is quite inert. I still don't buy the bit about painlessly reacting with anyone's fingertips, though.

We used to have a huge tub of sodium that had sat on the shelf for yonks. It was massively unpredictable in the water bath. My theory is that cracks had propagated over time. When it reacted with water then the cracks filled with hydrogen and literally blew each chunk of sodium apart.

It was fucking useless for demonstrating reactivity because it went off with a bigger bang than the potassium.
( ousgg is not seeking approval, Sun 11 Sep 2011, 18:28, closed)

It probably was..
Sodium then. Terrifying none-the-less.

As for the fingertips story, he seemed perfectly cheerful as half a dozen sparks popped on his finger tips. Could have claimed it didn't hurt as he wasn't the sharpest tool in the shed.

Overall, it was a fucking stupid thing to do!
(Jon_LTD Treat the world like a head!, Sun 11 Sep 2011, 21:08, closed)

I remember Mr. B the science teacher
finding a jarful that was "out of date"... Off we all toddled to the school pool to "safely dispose" of said jarful of Na. Apparently it reacts very well with chlorinated water, leaves a salt (EDIT: it wouldn't just be NaCl would it?) which is unpalatable to the school pool vacum & if properly stored in vegie oil pretty much never "goes off"?
(Misery McUglywife an attention seeking sociopathic fuckstain., Sun 11 Sep 2011, 21:28, closed)