Liquid-liquid extraction classroom demo?

Thinking about demonstrating the use of a separatory funnel for a class thing (speech class, not a chemistry class). Is there any combination of classroom-friendly solvents and solutes that will produce a nice visible result? Ideally I'd like two visually distinct phases, and a compound that will noticeably change the appearance of the phases during the extraction. I just can't think of anything offhand that will do the trick without involving some kind of gnarly organic solvents, toxic/expensive colored compounds, strong acids/bases, etc. Again, this is for a non-lab, classroom setting.

Any ideas would be really swell.

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OP here. Would cooking oil be an option? Oil would definitely give me the visually distinct phases I'm looking for. Not sure about what my solute would be though. Also, this will be a borrowed sep funnel, so I can't gunk it up too badly.

Just give a speech on why it is ok to own pit bulls or some MMA fighter like everyone else in your class, you nerd. You're just going to confuse everyone and be cringeworthy.

The speech has to involve a practical demonstration. That's the whole point of it. Most of the practical skills I have are from chemistry class. Also, extractions are probably the most intuitive and interesting thing I could show them, especially when you can literally see the stuff moving from one phase to another!

It's a fair point, though. If this falls through I'll show them how to iron a shirt.

You'd be surprised how confused the average pleb is by the simplest chemistry concepts.

I'm picturing some girl with her mouth open like "Fe(III)? That's umm, iron, right? What does the 3 mean again?"

This is a thing:

instructables.com/id/How-to-Salt-Out/

It also gives the benefit of being cheap as shit, recyclable, and clean.

>instructables.com/id/How-to-Salt-Out/

>greentext in an instructables article

Fucking lel

Identifying oxidation states, or even knowing that Fe is iron, is beyond this class. To be perfectly fair, it's communications, they're not expected to know chemistry. But "watch the neat color go from the top liquid to the bottom liquid" is something that anyone can enjoy.

Do this Something practical they can relate to everyday life use.

Does this work for ethanol, like cheap vodka?

>Use this hand to hold the jar in a vice like fashion and press the jar tightly against the counter top so it does not move. (Do not press so hard that you break the jar.)
>Use this hand to apply steady and controlled counterclockwise rotation motion to the jar lid.

Nice.

No. Ethanol still forms an azeotrope though.

>not knowing the difference between greentexting and using > for bulleting examples
fucking lel

oil and water?

Do a dirty DNA prep and show people the precipitation of sugars and protein and DNA at the interface between the alcohol and aqueous layers.

How about iodine in water/cyclohexane ?

Iodine in water : yellow-ish.
Add cyclohexane, which is colorless : bam, two phases, the yellow fades out a bit, and the cyclohexane turns violet.

OP here. So I bought some tincture of iodine (your basic first aid stuff) and added a splash to some water in a little glass jar. Poured in some olive oil and shook it as gently as I could. The iodine was extracted pretty nicely to the olive oil, although I may use a bit less and try to get the aqueous phase completely clear.

The issue is that the slightest rocking motion created lots of emulsion. Any suggestions on reducing this? Would salting the water help? It cleared up on its own after a while, but I'd like my phases to stay nice and separate throughout the shaking process.

My goal was to use only widely available and "safe" household chemicals, but honestly I may do this after all. I don't think it would be too outrageous to ask the lab tech if I could use a little bit of cyclohexane.

Put food dye in water and use water and oil. Easy, cheap, and safe

Wouldn't the dye be more soluble in water than in oil? If we're talking about your standard kitchen food coloring, that stuff is water-based (I think).

>"safe" household chemicals,

It's a fucking hexagon dude, how bad could it be?

>It's a fucking hexagon
literally everything organic haha

/thread

Just because you're completely reatrded and unravel to communicate your ideas to the non-science type doesn't mean OP is too.

It's a skill I've picked up talking to all my girlfriend's musician friends. I have to communicate CS to them somehow.

fucking benzene

>I'm picturing some girl with her mouth open like "Fe(III)? That's umm, iron, right? What does the 3 mean again?"
Ha ha ha it would be so amusing for someone who has clearly never taken general chemistry to have not absorbed the concept of oxidation states from the collective knowledge of society.

Almost as funny as being too autistic to recognize and prepare for the expected level of knowledge of your intended audience, and giving a speech full of hand-waving terminology you learned in a course they didn't take. Fucking brainlet.

Is that Ferrous or Ferric?

You're right, but you only need the dye in the water. Make it something bright like green and the natural colour of oil will contrast well enough

ferric

That wouldn't be an extraction, though. I could demonstrate the process but there would be no visible change in the water and oil layers. I want the dye to actually partition from the water to the oil so it's really clear that I am transferring something from one phase to the other.

I've decided to go with the olive oil, water and iodine. The salt helped, I think, and I used a wooden stick to break up the emulsion a bit. The result looks pretty cool: the aqueous phase ends up totally colorless, while the olive oil turns a deep yellow-orange. I may pour the oil through a funnel packed with some drying agent to get a nice, clear solution at the end.

I'm glad this got some interest. It was fun to fuck around with household chemicals. I kind of want to find more demonstrations like this.

Just use copper sulfate sol. and then saturate it with salt, and use canola oil. Im pretty sure you can get copper II sulfate from any fucking lab

Guaranteed no emulsions like pic related

The iodine is adding to unsat oil. Go with copper( II) gayfate. Its a pretty blue color

Alternatively, make a starch solution and add iodine so its purple-black. Be prepared for emulsions though

Or make a red cabbage extract (crush boil filter). Anthocyanins are your friends

Me again. Just take a bottle a DCM and splash it on their faces