How to make elemental iodine from sulfuric acid and sodium or potassium iodide. Warning: Reaction must be done outside or in a fumehood due to production of toxic gases including hydrogen sulfide. First, get your sodium or potassium iodide and completely dissolve it in a minimum of water. Then place it into an ice bath to keep it cold. Second, add concentrated sulfuric acid directly to the solution and constantly stir. As you add it will produce iodine. At first the mixture will become pasty and eventually liquefy. Once it's liquefied, pour it directly into cold water (the ice bath itself is useful for this) and stir it up. Then let it settle for ten minutes or so. The iodine will settle to the bottom so pour off the water and acid. The iodine will still be contaminated with acid so you'll need to add water and pour off several times to get out most of the acid. Filter it and now you have a solid plug of iodine. It's usable as-is for most purposes but you can purify by placing it in a beaker with a ice-filled round bottom flask on top. Then heat the beaker. The iodine will vaporize and deposit on the flask. A cool reaction is to take some iodine and pour magnesium powder over it. It will react to form a purple cloud of iodine vapor. If it doesn't react quickly enough, just add a drop of water.
"Bad Habits" (Parody of "Magic" by BoB featuring Rivers Cuomo) by Nathaniel Krefman THANK YOU TO THE CAST: Justin Bosch Phillip Cleves Nikki Cong Carl Ma Jennifer Padget Brock Roberts Alec Sexton Deborah Thurtle Oanh Tran Seychelle Vos Submission for UC-Berkeley MCB Follies 2010 (UC-Berkeley, Dept. of Molecular and Cell Biology) ________________________________________________ LYRICS: [Chorus] I've got bad habits in me. Everythin' I touch in lab it turns into mold. Everybody knows I've got bad habits in me. When glassware hits the floor, my labmates laughin' at me. Now everybody wants to change my habits. (I've got bad habits in me.) [Verse 1] This trick that I attempt will start a fire. Pick a day, any day, there ain't a shortcut I won't try. I'll need a borrow buffer, how 'bout yours with the sodium? I'll just open it up, and contaminate with it Plasmodium. I'll have you feelin' irritable, you'll think my skills are terrible, If pipette skills are heritable, my kids'll be hysterical. Even ma PI hadda say I got bad habits, and Anytime he sees an accident, says to me, "Man, what's happenin'?" What kinda flask you have it in'? Don't you know acid reacts with skin? You know that I won't ask again. Look what the cat be draggin' in. I know I'm more Steve Urkle than Steve Chu, "Did I do that?" So come on down to my bench. I'll let you see my habitat! [Chorus] I've got bad habits in me. (I've got bad habits, baby.) Everythin' I touch in lab it turns into mold. (You know it ...
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