(subtle groovy music)Im informing you, somebodys gon na look at my online purchase history and be like, shes printing costs and like, I suggest, technically I did.Making counterfeit cash is wrong and bad and prohibited and hard to do, and if you are looking for a how-to video, this is not it.Does that work, ACS Legal?Can we make the video now?These pens are filled with an iodine solution, usually something like potassium iodine to help the non-polar iodine liquify in water. If you swipe them on a piece of routine non-currency paper, which contains starch, it leaves behind a dark mark, and that is it.These pens are simply an easy reaction between iodine and starch.Now, the majority of regular paper like printer paper contains starch.If you recall our soft bread episode, some of the starches organized into long strands of glucose molecules called amylose, which can fold into helices.Inside the iodide, pen and iodine ions come together to form a triiodide complex.I understand, I know, lets go to the whiteboard.Okay, I got you.So iodine is the element, iodide is the ion, and the triiodide complex is three of em all together.Got it?Great.I think I got it.Equilibrium.This is important due to the fact that when you run the pen over the paper, these triiodide complexes slip inside the amylose helix and cause a dark purple or brown color.This is why you can get the same reaction on a starchy food like a potato chip.So iodine plus starch equates to a brown mark on regular paper, but currency paper isnt routine paper.Its really a mix of material fibers and includes no starch.So when you run the pen over a genuine bill, theres no color change due to the fact that theres no starch.Iodines color change depends on what it is dissolved in.As a strong, iodine is kind of a grayish metal with a purple vapor.If you include a bit of iodine solution into oil, you can see that truly beautiful kind of violet color.Theres a world in which thats purple.The color we see, of course, is light showing off of the molecules.Some light gets soaked up, moving electrons around in their molecular orbitals, and some light bounces off, and what we see is the light that bounces off.So if the wavelengths of light that get soaked up modification, the color we see can change as well.And iodines color modifications based on its solvent.For example, when added to water, iodine solutions turn from that sort of purple color into more of a yellow brown color.This is due in part to the interaction of electrons between the water and the iodine molecules.Weakly-bound donor acceptor complexes can form in between the iodine and the water, and this modifications how the electrons react to incoming light, altering the wavelengths of light that are soaked up, changing the color that we see.Now, when the iodine service in the pens reacts with starch molecules on paper, you get this kind of purple-brown color.And keep in mind how I said that it was most likely due to the fact that of the triiodide complexes slipping into the starch helices?Theres actually a bit more than just that going on here, and the research into the specifics is still ongoing, since its really cool.So the pens include a really dilute iodide-iodine service, which has little to no color.Now, there are I2 particles drifting around, triiodide complexes and potassium iodide.And if anything, this whole thing is just like, somewhat pale yellow.But when the triiodide molecules slip inside the amylose helices in starch, I2 particles tag along with them.Electrons that absorb inbound light can now quickly move back and forth in between the I2 and I3 molecules, due to the fact that theyre ideal next to each other, altering not simply the color of the iodine, however likewise the intensity.So now you can get these brilliant blues and dark browns that we see when we blend starch and iodine.Various lengths of polyiodine chains inside the amylose helices have actually been proposed from 3 to four, like we just talked about, to as high as 160.(correct buzzer dings)Cant capture me now, federal government mint.Now, this is how the traditional iodine clock response works, and Ive actually never ever done this experiment in the past, and it looks really cool, so were gon na do it.I did not come up with this version of the iodine clock response, Im following Nile Reds version of it, due to the fact that I have not done it in the past, and I thought this one looked good.So thanks, Nigel.Credit where credit is due.In one beaker, we have water, iodine, and vitamin C.Its colorless since that vitamin C suggests that we have iodide ions.In the other beaker we have water, hydrogen peroxide, and our old friend, starch.If we blend the two colorless liquids together, they at first stay colorless, however then bam.I believe my iodine concentration is a little too low.
Digging into the chemistry of counterfeit detection pens, this video covers various speculative efforts to customize their reaction with starch. It also talks about the broader context of counterfeit cash detection, highlighting the intricacies involved.Counterfeit detector pens utilize a starch-iodine response to recognize fake costs. Could you deceive them with chemistry? In todays episode, we dive into the chemistry of iodine, its color and its clock reactions, all while making a little additional cash on the side.Video Transcript: Lets say that we wanted to deceive these fake detection pens for science, how might we make this reaction not happen on typical paper?Yall, my search history is a mess.(subtle groovy music)Im informing you, somebodys gon na look at my online purchase history and resemble, shes printing bills and like, I mean, technically I did.Making fake money is wrong and bad and illegal and difficult to do, and if you are looking for a how-to video, this is not it.Does that work, ACS Legal?Can we make the video now?These pens are filled with an iodine solution, typically something like potassium iodine to assist the non-polar iodine dissolve in water. If you swipe them on a piece of routine non-currency paper, which contains starch, it leaves behind a dark mark, which is it.These pens are just a basic response in between iodine and starch.Now, most regular paper like printer paper includes starch.If you recall our soft bread episode, a few of the starches organized into long hairs of glucose molecules called amylose, which can fold into helices.Inside the iodide, pen and iodine ions come together to form a triiodide complex.I know, I understand, lets go to the whiteboard.Okay, I got you.So iodine is the component, iodide is the ion, and the triiodide complex is 3 of em all together.Got it?Great.I think I got it.Equilibrium.This is necessary due to the fact that when you run the pen over the paper, these triiodide complexes slip inside the amylose helix and cause a dark purple or brown color.This is why you can get the exact same response on a starchy food like a potato chip.So iodine plus starch equates to a brown mark on routine paper, however currency paper isnt regular paper.Its actually a mix of material fibers and includes no starch.So when you run the pen over a real expense, theres no color modification due to the fact that theres no starch.Iodines color change depends upon what it is liquified in.As a strong, iodine is type of a grayish metal with a purple vapor.If you include a little iodine service into oil, you can see that really lovely type of violet color.Theres a world in which thats purple.The color we see, obviously, is light showing off of the molecules.Some light gets absorbed, moving electrons around in their molecular orbitals, and some light bounces off, and what we see is the light that bounces off.So if the wavelengths of light that get absorbed change, the color we see can change as well.And iodines color changes based on its solvent.For example, when added to water, iodine options turn from that sort of purple color into more of a yellow brown color.This is due in part to the interaction of electrons in between the iodine and the water molecules.Weakly-bound donor acceptor complexes can form between the iodine and the water, and this modifications how the electrons react to inbound light, changing the wavelengths of light that are taken in, changing the color that we see.Now, when the iodine service in the pens reacts with starch molecules on paper, you get this kind of purple-brown color.And keep in mind how I said that it was most likely because of the triiodide complexes slipping into the starch helices?Theres really a bit more than just that going on here, and the research study into the specifics is still ongoing, due to the fact that its really cool.So the pens consist of an actually dilute iodide-iodine service, which has little to no color.Now, there are I2 particles drifting around, triiodide complexes and potassium iodide.And if anything, this whole thing is simply like, a little pale yellow.But when the triiodide particles slip inside the amylose helices in starch, I2 molecules tag along with them.Electrons that take in inbound light can now easily return and forth in between the I2 and I3 molecules, due to the fact that theyre best beside each other, altering not simply the color of the iodine, however also the intensity.So now you can get these bright blues and dark browns that we see when we mix starch and iodine.Various lengths of polyiodine chains inside the amylose helices have been proposed from three to 4, like we simply discussed, to as high as 160. Lots of variability.A 2022 group examined and suggested that the brief chains may get in the helix and then reorganize, triggering longer chains, and also possibly triggering modifications to the structure of the helix itself.The interaction also alters based on the length and the structure of the amylose helices, how much water is around, how the starch itself was purified.There are a lot of things here that might affect exactly what color takes place when you run that pen over the paper.Anyways, this is all cool, but what if we wan na actually stop this interaction from happening?We cant pull the iodine outta the pens, so instead, lets see if we can take a stab at getting the starch out of the paper.First up, starch is a polymer of sugar molecules, so we could attempt heat to break that down.Starch breaks down starting at around 280 degrees Celsius, which is about 536 degrees Fahrenheit.But my oven only goes to 500, and the ignition temperature level paper is around 233 Celsius or 451 Fahrenheit, so Im gon na try and set my oven to 425 and see if maybe we can break it down a little bit, however without catching it on fire.(pan bangs)Dont try this at home.I also have a fire expert on hand, just in case.(container rustling)(incorrect buzzer dings)But heres why biochemistry is my favorite.Fight me, George.Enzymes catalyze reactions by decreasing their activation energy, and there is an enzyme that catalyzes the breakdown of starch.Amylase.Amylase takes that reaction that takes place at 233 degrees Celsius and makes it happen closer to about 65 to 75 Celsius, which is way more reasonable.Now, your spit actually includes a great deal of amylase to break down the starches in food.So what Im gon na do is Im gon na take this paper and Im gon na lick it, no, Im not.Im not gon na do that.Instead, Im gon na take this amylase that I bought from the web and include 1/2 a teaspoon per gallon of water and simmer our paper in it at about 70 Celsiusor 158 Fahrenheit.Amylase breaks down starch chains into smaller sugars like maltose and glucose.Theres bubbles forming at the top, and I really am wondering if those bubbles resemble, little, sweet, I mean for sure its cause the water is warming up, but like maybe were in fact breaking down some starch into some sugars there.Eh, no.Maybe it worked a little.No.(incorrect buzzer dings)Now, yeast also develops and utilizes amylase, so if you d like to do this a much smellier way, you could try that too.(incorrect buzzer dings)Alternatively, we might attempt obstructing the iodine from engaging with a starch rather than breaking it down.Now, we might attempt and do this physicallywith something hydrophobic, like hairspray.(hairspray whooshes)Oh-ho-ho-ho, that did not operate at all.It nearly made the reaction faster.Hairspray is a no.(inaccurate buzzer dings)Or you could try vitamin C.Vitamin C, AKA, ascorbic acid, minimizes iodine into iodide ions, which are essentially colorless in solution.So you get I2, 2I minus.These hydrogens pop on over here.Reduction, chemistry.So we can spray our expense with a little bit of vitamin C liquified in water, let it dry, and then try the pen.Woo.The vitamin C worked.(right buzzer dings)Cant catch me now, federal government mint.Now, this is how the timeless iodine clock reaction works, and Ive in fact never ever done this experiment before, and it looks truly cool, so were gon na do it.I did not develop this variation of the iodine clock response, Im following Nile Reds version of it, because I have not done it in the past, and I believed this one looked good.So thanks, Nigel.Credit where credit is due.In one beaker, we have water, iodine, and vitamin C.Its colorless because that vitamin C suggests that we have iodide ions.In the other beaker we have water, hydrogen peroxide, and our old friend, starch.If we blend the two colorless liquids together, they initially stay colorless, however then bam.I think my iodine concentration is a little too low.(intense tone beeps)(brilliant subtle music)Oh, the other one, the one off cam simply turned.Theres hope, theres hope, theres hope.(instructor laughes)Bam, they develop into a dark liquid.This is since there are several reactions happening here.The hydrogen peroxide turns the iodide ions back into I2 or iodine, but as long as theres vitamin C around, the iodine keeps being lowered back to iodide.But ultimately, the vitamin C goes out, the I2 forms up, comes together with some other I-minus ions to form those triiodide complexes we discussed before.Those hang out with starch, and bam, color.So freaking cool.What was this video about again?Right, fake money.Because none of this occurs in genuine currency paper, since theres no starch in it.US currency paper is made by Crane & & Co.They were handpicked, no lie, by Paul Revere, to makethe very first US currency, and theyve simply stuck ever since.The paper also has blue and red colored filaments running through it, making it tough to replicate, and Crane & & Co wont offer it to you.But this stuff is some paper that I purchased off of Amazon, so you can purchase a paper that might already deceive a tired, underpaid cashier simply attempting to complete their shift and check your bill.Right, its absolutely a various color from the printer paper.So theres printer paper and after that Amazon paper.Theres the real bill, and I dont think its fooling anybody.I bet they spray it with a little starch for this purpose.And most genuine counterfeiters arent buying things like this.Theyre bleaching little denomination costs to get the best paper, and after that printing bigger denominations on it.So these pens are among the weakest methods of fake detection for a variety of reasons.So was all of this for naught?I mean, no, the chemistry deserved it.You discovered something, didnt you?I did.I actually have not tried this pen on this paper yet.Also, enjoyable fact, this paper has red and blue filaments running through it.Like, you can just purchase with red and blue fibers in it.What are they doing?
