how is caffeine extracted using chloroform?
595789
To separate caffeine, you could use HPLC, LC, GC, or TLC, which are all chromatography techniques. \n\nIf you do a physical separation, a polar organic solvent would do nicely.\n\nTo make sure that you are actually extracting the chloroform, suspend the separatory funnel on a ring off of a ring stand. Wait 10 mins. You'll see two layers, a top layer and bottom layer.\n\nChloroform has a density of 1.48 g/mL and water has a density of 1 g/mL, so the chloroform will be the bottom layer. Use the sep funnel to recover all the chloroform. At the end, I'd run saturated sodium chloride through the chloroform and separate that, to clear any nonorganics from the chloroform.\n\nAfter that, you can put the chloroform on a rotavap or do TLC to see if you have caffeine and caffeine only (doubtful)
160714
Chlorofluorocarbons (CFC) are a group of simple alkanes (compounds of carbon and hydrogen) that also contain both chlorine and fluorine atoms.  They were widely used as propellant gases, dry cleaning solvents and refrigerants (Freon, and others).  As gases, these compounds often rise into the upper layers of the atmosphere where they react with sunlight to break down, releasing chlorine and fluorine atoms.  This process is called photodissociation.\nFree halogen atoms (such as chlorine and fluorine) react readily with ozone.  Their use over the last several decade has lead to a depletion in the ozone layer which protects our atmosphere from harmful UV radiation.  The international agreement called the Montreal Protocol is the reason that their use is prohibited.
1014953
Yahoo!answers & caffiene.
69447
In a 210ml cup:\n\n   Tea, brewed, imported -   60mg\n   Tea, brewed, U.S. - 40mg\n   Tea, instant - 30mg\n   Mate -  25-150mg\n\n"Caffeine content is also affected by the length of the infusion in water. Black tea infused for 5 minutes yields 40-100 milligrams, whereas a 3-minute infusion produces 20-40 milligrams, or half as much. Twenty cups of green tea yield 240 milligrams, or about 12 milligrams per cup.\n\nBecause tea bags contain broken leaves of smaller size, they produce an infusion with more caffeine than loose tea does. This is also true of very fine loose tea."
396313
Chloroform.  It's an anesthetic (or, used to be).
707129
I think you're off...sorry. Caffeine accelerates metabolism of animals that have nervous system. It doesn't affect the cells, it affects the nervous system that controls the metabolic rate of, for example, mammals. It works pretty much teh same way as adrenaline.\nOn the other hand, euglena cysts don't have reduce metabolic rate: the dont have ANY metabolism going on. They're just a mass of molecules disposed in a perfect way that when triggered by the environmental condition, they start  working. Like a car motor. To do this, the euglena must in fact be very metabolically active in order to produce a lot of stuff and make a lot of changes to prepare for cysting. The stimuly are very specific: water and glucose. (and lack of water or glucose to form teh cyst). So i doubt that caffeine will affect, unless you put so much into the water that it becomes a poison, in which condition it may form a cyst (not by affecting the metabolic rate though)\nYou migh want to rethink your project and try to find out how much caffeine is pisonous for euglena and can it form cyst to protect itsefl from this condition?\nThe other thing about working with petri dishes: If it's a solid medium, nutrients will probably drop dow very fast, in which condition the euglena will form cysts. You won't be able to know how much the lack of nutrients made it unvulnerable to caffeine. Try to use a system that is more stable, like liquid medium, in which you can somehow trigger a cyst forming event. That way you will have more control.\nGood luck
457656
A fatal dose of caffeine has been calculated to be more than 10 grams (about 170 mg/kg body weight) - this is the same as drinking 80 to 100 cups of coffee in rapid succession - not an easy thing to do.\n\n\nhttp://staff.washington.edu/chudler/caff.html
159750
Commercially:\n=============\nFractional distillation of liquified air. This method involves:\n\n1. Liquifying air which is mostly Oxygen and Nitrogen\n2. Heating liquid air.\n3. Cooling at different temperatures to collect different gases.\n\nOne of the major bi-products of this method is Nitrogen. \n\nLaboratory:\n===========\nHeating some oxide in presence of a catalyst or electrolysis.
756504
An apparatus for reflux uses a round bottom flask for boiling the reaction contents and allowing the vapours to condense in a water cooled condenser attached vertically above the flask.  The vapours condense and run back down into the flask in order for them to boil again.\n\nIt is a method for boiling a solvent, or mixture, under conditions of near constant volume without the need to "top up" the vessel with fresh solvent.
1150323
Methcathinone can be synthesized by oxidation of (pseudo)ephedrine with (di)chromate salts, or via Jones reagent.Here is the synthesis via Jones reagent:\nOxidizing the Alcohol to a Ketone\n1.068 grams (just over 1 gram) CrO3 are added to 0.92ml H2SO4, and distilled water is added to bring the total volume to 4ml. 2 grams of pseudoephedrine are dissolved in 20ml acetone, and cooled in an ice bath. The Jones reagant is slowly added to the pseudoephedrine, dropwise and with stirring. The mixture becomes a reddish brown.Since we used just about the exact number of molecules required, and under very mild conditions, the reaction will proceed slowly, but very smoothly. Just let the ice melt and the stirred solution warm over night.\nExtracting the Ketone\nAbout 12-18 hours later the reaction is complete, the color is now a very dark green. We now have to neutarlize and extract our ketone. Add about 20mL of water, and chill in an ice bath. Dropwise and with stirring add about 1 gram of lye (Sodium Hydroxide - NaOH) in a solution with as little water as possible (highly concentrated). Check the pH regularly, and stop at pH=12. The now basic solution is shaken with 50ml of toluene. Allow to stand and two layers will form. The ketone will move into the toluene layer. Let the mix settle and remove the acetone/toluene/ketone and put it aside. Add another 50mL portion of toluene to the aqueous (water-based) portion, shake, filter (which breaks the emulsion and removes some chromium salts), and remove and put aside the toluene. Ensure that pH is still 12, and repeat again with another 50mL portion of toluene.Combine the three toluene extractions and evaporate them with a hair dryer. The result is the impure ketone of pseudoephedrine, also know as methcathinione or ephedrone.We used very gentle oxidation, neutralization, extraction, and evaporation conditions. Shortcuts can be used (no ice, evaporate with some heat, etc.), but good lab practice is never to stress the substrate needlessly. So we were careful.The raw "dirty" methcathinone weighs about 1.7 grams.It is purified by adding just enough tolene to redissolve it. Some particles will not dissolve, and are left in the drying dish. The toluene is filtered to remove any additional particles, poured back into the separation funnel and shaken with an equal amount of distilled water. This removes any small amount of water solubles. The toluene is put into a clean dish and dried once again. The impurities are more soluble in acetone than the ephedrone, so a very small amout of acetone is added, and sloshed around. Pour this off into the waste (original green mix). What's left is a little over 1 gram (about 60% yield) of relatively pure, slightly off-white methcathinone.\nBetter chemists can expect a much higher yield. This is a general procedure. The example given -Pseudoephedrine or Ephedrine to Methcatinone - is for illustrative purposes only. Oxidizing cold pills is illegal, and makes a lousy drug anyway
721022
Well, I do not know that syllabus.  You will need to sift useful answers.\n\nI would use:\n\ndifferent solubility in solvents\ndifferent boiling points\nrecrystallise one out of a mixed solution\n\nYou might be at too junior a level to know about ion exchange resins, and other chromatography techniques.
286363
Chloroform is often used as a tool in kidnapping, especially in books and movies. The use of chloroform to knock out a victim was a recurrent plot device in 1980s television series such as Knight Rider and The A-Team, as well as in Peter Jackson's King Kong (2005). Typically, the villain would spill a few drops from a small bottle onto a handkerchief, and then sneak up behind the victim. When the handkerchief was held over the mouth of the victim, they would struggle for a few seconds before slumping unconscious. After-effects were usually limited to a brief headache. In reality, a dose far greater than a few drops inhaled over a short period of time would be required to knock somebody out. Such a dose could also be lethal.
917410
It would take over 80 MONSTER energy drinks to kill someone from caffeine. So just drink your MONSTERS or Rockstars or w/e and just stay cool, chew gum to get the smell of alcohol off your breathe.
1132950
Caffeine is soluble to some extent in both water and chloroform, however water and chloroform do not mix.  Therefore if we have an aqueous solution of caffeine in physical contact with some liquid cloroform (as in a separation funnel) then some of the caffeine will move from the water and spread into the chloroform.  We can represent this kind of reaction by the following equation:\n\ncaf(aq)  <-->  caf(ch)\n\nThe caffeine can move back and forth between the water(aq) and the chloroform(ch). We say that the caffeine partitions between the water and the chloroform.   Just like any other reaction there is an equillibrium associated with the partioning reaction, and the equillibrium constant (it is called a distribution constant or partition constant in this case) is defined in the same way as for other reactions:  concentration of products over concentration of reactants.  In this case the distribution constant would be given by:\n\nKd = [caf(ch)] / [caf(aq)]  or rearanging  [caf(aq)] * Kd = [caf(ch)].\n\nSuppose we have an initial volume of aqueous caffeine solution V(aq), and we mix it with a volume of chloroform V(ch).  After we have mixed them and let them come to equillibrium.  There will be a certian concentration of caffeine in the aqueous phase of [caf(aq)], and a certian concentration of caffeine in the chloroform of [caf(ch)].  \n\nThe moles of caffeine in the water can be calculated by the following:\n\nmoles caffeine in water = V(aq)[caf(aq)]\n\nThe moles of caffeine in the chloroform can be calculated in a simmilar manner:\n\nmoles caffeine in chloroform = V(ch)[caf(ch)]\n\nThe total moles of caffeine in the system will be the moles of caffeine in the water plus the moles of caffeine in the chloroform.\n\ntotal moles caffeine = V(aq)[caf(aq)] + V(ch)[caf(ch)]\n\nNow, the fraction of caffeine left in the water (fraction left = fl) is the moles of caffeine in the water at equillibrium divided by the total moles of caffeine in the system as shown below.\n\nfraction left in water at equillibrium = (moles caffeine in water) / (total moles caffeine)  or in other words:\n\nfl = V(aq)[caf(aq)]  / (V(aq)[caf(aq)] + V(ch)[caf(ch)])\n\nUsing the equillibrium expression we may make the following substitution in the above equation:  [caf(aq)]*Kd = [caf(ch)].\n\nsubstituting this in we get the following:\n\nfl = V(aq)[caf(aq)]  / (V(aq)[caf(aq)] + V(ch)[caf(aq)]*Kd)\n\nNow we see that all the [caf(aq)] factors cancel leaving us with:\n\nfl = V(aq) / (V(aq) + V(ch)Kd)\n\nSince we are not actually interested in the fraction left but are rather interested in the fraction extracted (fe) the equation for the fraction extracted will simply be one minus the fraction left or:\n\nfe = 1 - fl = 1 - V(aq) / (V(aq) + V(ch)Kd).\n\nIf a percent is desired we simply multiply the fraction by 100% or:\n\n%fe = (1 - V(aq) / (V(aq) + V(ch)Kd))*100%.\n\nFor this particular problem you want an 85% extraction, you have 120ml of aqueous volume, and a Kd of 0.0714.  Putting these values into the above equation we arrive at:\n\n85% = (1 - 120ml / (120ml + V(ch)0.0714))*100%.\n\nAll that is left to do is solve for the volume of chloroform needed (V(ch)).  I will leave the rest of the algebra to you, but I will give you a multiple choice so you can check your answer.\n\nVolume of chloroform needed is:\nA) 11.9ml\nB) 97.5ml\nC) 524ml\nD) 982ml\nE) 2210ml\nF) 9520ml\nG) 10500ml\nH) 53600ml
366275
(m)\n\nCaffeine is found in Coke, Jolt Cola, coffee and chocolate.\nYoung people and teenagers can consume high intakes of caffeine through cola drinks and ice coffee. High doses can cause heart arrhythmia.\nThis usually happens at intakes of more than 600mg of caffeine. This could be equivalent to 10 cups or more of coffee. Caffeine appears to be addictive. \nCaffeine is a stimulant that is often consumed to enhance alertness and concentration. Concentration of caffeine peaks in the blood within 30 to 60 minutes after the first sip and the effects last about four to six hours. Moderate consumption of caffeine is considered to be about 200-300 mg. (about the equivalent of 2-3 cups). Drinking too much caffeine (especially for people who don’t normally consume much) can cause nervousness, anxiety, sleep problems and a temporary increase in heart rate. Excess consumption may increase the risk of headache and elevated blood pressure. \n\nThe amount of caffeine in drinks varies greatly. An 8-ounce cup of brewed coffee contains 65 to 120 mg. of caffeine. However, some coffees may contain as much as 250 mg. of caffeine. A one-ounce serving of espresso contains about 30 to 50 mg. of caffeine. By comparison, a cup of decaf coffee (which is really not caffeine-free) contains 2 to 40 mg. of caffeine. An eight-ounce cup of brewed tea contains 20 to 90 mg. of caffeine. Iced tea tends to have less caffeine, ranging from 24 to 31 mg. of caffeine for an 8-ounce glass. Hot chocolate (8 ounces) contains 3 to 32 mg. of caffeine and a glass of chocolate milk contains 2 to 7 mg. A one-ounce serving of milk chocolate contains about 1 to 15 mg. of caffeine, while dark, semi-sweet chocolate has 5 to 35 mg.
835846
probably ether or chloroform
730950
with lots of caffeine and a bit of patience.