Chemistry trivia

Here's some random junk I found out today. Doubtless they will be the only things I can think of when actually facing exams.

1. The average adult human contains 25g of magnesium.
2. Owing to its weak metallic bonds and light BCC structure, sodium does, in fact, float.
3. Beryllium compounds are some of the most toxic substances known to man.
4. Below a certain temperature white tin changes to grey tin. White tin was previously used as a solder on cans; it's thought that bringing these cans on some arctic expeditions is what led (among other things) to the expeditions' failure.
5. Cesium and water make a very entertaining combination.
6. HF, being a weak acid, doesn't hurt when you spill it on your skin. It does, however, continue through your body until it reaches bone, where it leaches calcium from your bones and blood until you die of cardiac arrest.
7. Wouldn't #6 make an awesome House episode? House could figure it out like two seconds before the patient dies and then he dramatically rushes in and starts rubbing elemental calcium on the patient's feet or something while Cameron goes "HOUSE WHAT ARE YOU DOING" and then the patient suddenly comes back to life and all is well and then he and Wilson trade quips as the end credits roll. Oh wait that's every single episode of House ever.
8. The phosphorous is on the side of the matchbox, not the match head. Unless you have strike anywhere matches, then it's on the match head.
9. White phosphorous is so energetically unfavorable, it's like the most retarded allotrope ever.

More as studying warrants.