Absorption spectroscopy and acetic acid

Absorption spectroscopy and acetic acid The absorbance of light, wavelength 632nm, was measured in an indicator solution at varying pH, and varying concentration, allowing for a Beer-Lambert plot to be constructed. This was then used to measure acetic acid uptake at the surface of deionised water and octan-1-ol coated water, allowing pH, and hence concentration, to be calculated from absorbance of the liquid. Introduction Surfactants are molecules which are able to form a surface across a liquid, and stop the interaction of foreign molecules with the solution without interacting with these molecules first. These are extremely useful since they often contain a hydrophobic and hydrophilic aspect, which interact differently to different molecules. Surfactants are used in the manufacture of paper, textiles and construction among others.[1] They are the main ingredient of detergents and they allow non-polar molecules to dissolve in polar molecules, such as oil into water. On the surface of the liquid, the surfactant will interact slightly differently. It will create a surface of hydrophobic tails. This will stop polar molecules from entering the liquid, since the liquid will appear to be a poor solution for the polar molecule to interact with. They also increase decrease tension of the liquid.[4] This barrier is expected to stop the acetic acid, used in part 3 of the experiment, interacting with the water solvent. If it does interact, the pH of the solution will lower due to acetic acids presence, and the indicator will show a change in colour. If no acetic acid enters the solution, no change should be observed or measured. Experimental Using de-ionised water, a reference light intensity was recorded. A 250ml solution (1) of 0.005% wt bromocresol green was then prepared, and absorbance was measured. 100ml was removed, and the pH adjusted using 0.1M sodium hydroxide and glacial acetic acid, and absorbance was noted at pHs between 3-6 at 0.3 increments. 50ml of remaining solution (1) was further diluted to solutions of 0.0025%, 0.00125%, 0.000625% and 0.0003125% concentration. Spectroscopic analysis of these concentrations was made, and a Beer Lambert graph plotted. A solution of unknown concentration was then spectroscopically analysed and its approximate concentration determined. This solution was then enclosed in a container with acetic acid, and spectroscopic readings taken every 30 seconds. This was repeated with fresh solution, with the addition of 0.2ml of octan-1-ol to the surface of the cuvette. Results The results for the pH change showed a curve, going from lower pH on the left to high pH on the right. This is a more quantifiable way of showing that as the Bromocresol turned blue at higher pH. This shows absorption toward the end of the spectrum of lower energy, (ie higher wavelength). So as pH increased, the absorbance of Bromocresol at 632nm increased too as it became blue. The next aspect of the experiment was to analyse how concentration affected the absorbance of Bromocresol green. As concentration of bromocresol green was altered, it was possible to draw a Beer-Lambert plot detailing how the absorption of the light changed with concentration of the Bromocresol Green. As would be expected, there is a straight line relationship between Bromocresol concentration and Absorbance except at higher concentrations, where the solution plateaus and becomes non-linear. Excluding this end point it is possible to derive the gradient, and hence the value of ?L. This was determined to be 36600. The Bromocresol solution of unknown concentration transmitted 0.222, making a LOG(Io/I) value of 0.67. Dividing this by the gradient gave the Bromocresol solution concentration to be 4.5710-6moldm-3. From this it is possible to determine the acidity of the solution using the Beer-Lambert plot as given above. Using an original pH, it is then possible to determine the concentration of the acetic acid on top of this, using simple equations associated with pKa and pH. From the information of Ka and pH, it is possible to calculate the concentration of acetic acid in the solvent. Error analysis Using error analysis and standard errors of instrumentation used, it is possible to construct the same graphs as above but with error bars. These are shown below. Discussion The calculations and graphs suggest that coating a solvent in octan-1-ol would encourage uptake of acetic acid, rather than inhibit it. This may be due to dimerzation or trimerzation of acetic acid (1) as it evaporates from the surface, making it more soluble in the partially polar octan-1-ol solution. Single carbon-oxygen bonds display less polarisation than carbonyl bonds do, and so it is likely that in this dimerised arrangement acetic acid more readily dissolved in the oil, in addition to acetic acid readily dissolving in organic solvents. Because of these reasons it readily crossed over from the relatively non-polar octanol to the polar water solvent, decreasing the pH of the Bromocresol containing solution in both the uncoated and octanol coated solutions. It is, however, most likely that the experiment was not successful. Alternative indicators, such as NH3, would have readily dissolved in water and increased the pH of the solution. It would also not have been able to dissolve in the octanol due to the higher polarity and availability of the nitrogen lone pair. Because of this it would have been a better indicator of the presence of a surfactant than acetic acid. Acknowledgements I would like to thank my demonstrators M. Azwani Mat Lazim and Miss Olesya Myakonkaya for their advice on the experiment. References R. J. Farn, Chemistry and Technology, Blackwell Publishing (2006) pp. 6. L. L. Schramm, Surfactants: fundamentals and applications in the petroleum industry, Cambridge University Press (2000) pp. 7. R. J. Farn, Chemistry and Technology, Blackwell Publishing (2006) pp. 6. K. S. Birdi, Handbook of surface and colloid chemistry, CRC Press (1997) pp. 338. P. Atkins, J. De Paulo, Atkins Physical Chemistry 8th Edition, Oxford Publishing (2006) pp. 432. P. M. S Monk, Physical chemistry: understanding our chemical world, John Wiley Sons (2004) pp. 225. V. H. Agreda, J. R. Zoeller, Acetic acid and its derivatives Volume 49 of Chemical industries, CRC Press (1993) pp. 96.

The Cellar Of Doom

Alesha let out a long, heavy sigh. She couldn't believe she was stuck in an old hotel in Lincoln, Maine, USA. It was the Summer Holidays and she had come to America with her mum, dad, and her annoying younger brothers Ashley and Scott, who were six and seven. Scott and Ashley weren't the quiet sort of kids. They tended to excited over anything, and were always hyper. The Miller family were staying at The Stars And Stripes Hotel, which was really old and boring. Alesha would much rather be back at home in England, even it was raining all the time there. Alesha had only been there for two days, and had already taken advantage of the ‘fantastic facilities'. There was the ‘amazing' pool and spa, the ‘fabulous' arcade and the ‘wonderful' multi – sports court. Alesha couldn't see what was so fantastic about a dirty pool, an out-of-order spa, two fruit machines and a large pitch of mud with a few goalposts. It was going to be a very long and boring two weeks. She had been out ‘exploring' the creepy, old hotel trying to find some kids around her age. Alesha was 14, so it was quite easy really, as there were loads of fed up teenagers staying at the old place. â€Å"Alesha, we're going out!† her mum called. â€Å"Cool, lets go to Detroit, or Hollywood, or†¦.† â€Å"No, I mean me and your father are going for a meal. We're going to find a place to eat. OK?† â€Å"What?† Alesha protested. â€Å"That's not fair. You mean me, Ash and Scott have gotta stay here?† â€Å"That's right. We'll be only be gone for about three hours. We are not going far, we are still staying in Lincoln, don't worry!† â€Å"But mum†¦Ã¢â‚¬  â€Å"No buts, OK? Now, be good.† Alesha sat on the fraying green couch, and looked around the dreary brown and yellow room. ‘The colours in here are awful. They so don't match!' she thought. She picked up her magazine and started to read the article about her favourite rapper, Eminem. She glanced at the clock. Her parents had only been gone for ten minutes. She heard a loud banging noise. â€Å"Ashley, Scott, please SHUT UP! Stop that banging NOW!† she shouted. â€Å"Alesha, it wasn't us!† Scott called. â€Å"Whatever! Now, just shut up!† She flicked on the old television and picked up the dusty remote control. The room hadn't been cleaned for ages. The floor had cigarette stains all over it, and as for the curtains, there was no point in having them there, because they were so ripped and frayed, they were almost non – existent. The banging noise was really annoying her now, and she yelled at her brothers to shut up, but they denied making the banging sound. She threw down her magazine and started to watch the TV. There was an image of a man building a brick wall in what looked a cellar. There was also a middle-aged lady with him. She looked really bewildered. Then the man turned to her and started beating the lady with a shovel. Boring! Alesha pressed the CHANNEL UP button. ‘Wonder how to get TRL on this thing?' Alesha wondered. The same image was on the screen. What? Alesha pushed down hard on the control. Maybe the button had got jammed. Now the woman was crying out in pain, and blood was staining her pale blue dress. She was screaming STOP! STOP! But the man obviously had no feelings, for he kept beating her, his shovel bright red, his face with an evil grin, his grey eyes frostily staring at the frightened woman, and the horror on the woman's face. Alesha was horrified, and pushed the button again. By now the woman was dead, and the TV still wasn't working properly. Alesha watched as the man started digging a hole, maybe a grave, in this thing that looked like a fireplace, but filled with soil and coal. Then Alesha heard a banging, and she wasn't sure whether it was on the TV or the same one as she had heard before. Alesha was really frightened, but she was almost glued to the screen. She wasn't sure what it was, but it was like there was a special force, keeping her transfixed to the terrifying images. She tried to pull away, but she couldn't. She watched as the evil man kicked the dead body into the make – shift grave. After a while, the man had covered the woman with soil and coal. He carried on building the wall. Alesha had snapped out of her trance, and tried the same button again. But when she pushed the button, nothing happened. What was going on? Maybe the remote wasn't working properly. That was why the sick program wouldn't go away. She stood up, and kept hearing continuous banging. Maybe it was next door or something. She was getting quite scared now. She realised that it was 6:30 pm, and that her parents had been gone for an hour. She couldn't bear to be alone now, so she called to her brothers. She turned the TV off. â€Å"Oi, come ‘ere, now!† she called out, agitated. When they didn't answer, she went to investigate. She realised that they were asleep in their beds. ‘Typical. Asleep at 6:30! Lazybones!' she thought. ‘Well, they must be quite tired after the football this morning.' Then there was a knock at the door. Thinking it was her parents, Alesha hastily opened it. â€Å"Hi!† said a voice. She saw it was her new friends that she had met in the pool yesterday. â€Å"Hi Marshall, hi Justin, hi Mel!† Alesha cried. Marshall was from Detroit, Justin was from California and Mel was from England. They were bored too. â€Å"Wanna come out with us? We are sooooo bored, and we're jus' wondering whether you wanna come and jus' like wander around here.† Justin said. â€Å"I can't, I gotta look after my brothers.† She replied. â€Å"Go on!† Mel pleaded. â€Å"Well, only quickly. Scott and Ash are asleep anyway.† Alesha stepped out with her friends, and realised that she had about two hours before her parents got back. â€Å"So where we goin'?† Alesha asked. â€Å"Dunno!† Mel replied. They walked around, and found a set of stairs leading downwards. Alesha had forgotten about the TV incident, because she was happy that she wasn't alone anymore. There was a NO ENTRY sign on the door. Alesha's phone beeped. It was a text message. It said: HI ALESHA HOPE U R LOOKIN AFTA UR BRUVZ. WE MIGHT BE BAK L8R, MAYB @ 9:30. HOPE U R OK. IF U GET WORRIED JUS CALL US. C U L8R MUM N DAD XX : ) Alesha felt a bit guilty leaving her brothers alone now, but pleased she was out of the boring, stuffy hotel room. Marshall turned the NO ENTRY sign over so that it looked like a blank piece of card. They followed the stairs down, and realised that it was a cellar. It was pitch black. Alesha heard a very familiar noise. â€Å"Uh†¦.is there a light in ‘ere?† Mel asked. â€Å"Hey, guys, y'hear that?† Alesha questioned, totally ignoring Mel. â€Å"What, the banging? Yeah, I think†¦.† Justin said. â€Å"SHHH!† she whispered. Sure enough, there was a banging coming from somewhere in the room. Marshall searched the wall with his hands to find a light switch. He found one, and flicked the switch on. BANG! BANG! â€Å"Marshall†¦Ã¢â‚¬  Mel said. The banging got louder. â€Å"It's nothing, OK guys? Leave it. We're fine! Hey†¦.Look, a video camera! Its one of them ones that came out about five years ago, you know, a pocket one! They are worth loads!† Justin shouted with excitement. He went over to examine it. It was about 10cm in height and 5cm in width. Justin had seen it hidden in a small hole in the wall. It was plugged in though, as if someone had connected it to something. Alesha noticed that something had been boarded up. â€Å"Hey, check this out, I wonder what's behind this?† â€Å"Er, probably nothin' interestin'† Marshall answered. He started to kick the board down, with Justin still examining the video camera. Mel and Alesha just stood there talking. Once Marshall kicked the down the board, there was a wall which was about 2 metres high. â€Å"Hey, look over here!† he cried with excitement. â€Å"What it is?† Mel asked. â€Å"Dunno. I'm gonna climb over it and see what it's hiding.† He started to clamber over it, but the wall obviously hadn't been built properly, because it collapsed almost straight away. Marshall tumbled to the floor, and realised he had landed right next to something that made him feel quite sick†¦ â€Å"Ugh, Justin, it's a skeleton! How did it get down here?† Justin screamed. â€Å"OH MY GOD!† Mel cried when she saw it. â€Å"Cool†¦Ã¢â‚¬  Marshall marvelled. â€Å"Yuk! What we gonna do?† Alesha shouted out. Then Alesha remembered the video. â€Å"Justin†¦.† she called out. She ran over to the video camera. It was true. The video camera was connected to a TV somewhere in the hotel. Her TV. The shocking images that she had been watching earlier had actually happened. She explained to the others what she had seen earlier. But how could the banging be explained? Once Justin had gone to reception to find somebody, the once isolated room was filled with police, hotel staff and detectives. The police questioned the kids. Mel thought they would get told off for entering the cellar without permission! They didn't though. Although Alesha got told off for leaving Ashley and Scott on their own, she didn't really mind because it had been an adventure for her. Months the woman was named as Ann McKenzie. The police confirmed that Alesha's story was true. What had happened was that years ago, Ann knew that her fiancà ¯Ã‚ ¿Ã‚ ½ would kill her, because he was so violent, and every time she left him, he would hunt her down and beat her up. Every year they came to Maine, to The Stars And Stripes Hotel, and he kept dropping hints about death and that he would kill her once they were in Maine. Because they were from California, he thought that he wouldn't be caught because of the distance. She had no escape. So she invested in a mini camera so that he could be caught. Ann cleverly connected the camera to a TV, which happened to be in Alesha's room. Since the hotel had been closed for the last three years due to health and safety reasons (Alesha wondered what it was like before the inspections), nobody would have noticed. Then Ann's fiancà ¯Ã‚ ¿Ã‚ ½ (later named as Daniel Durst) beat her to death and sealed up her body up in the fireplace. Because the camera was a mini one, Daniel didn't notice it. Ann was removed from the Missing Persons list, and because Daniel's face was seen on the camera, the police caught him, and gave him a life imprisonment. The kids were given medals because they were quite brave. Alesha wasn't sure, but she had a funny feeling the banging noise was the ghost of Ann McKenzie, trying to get the attention of holiday – makers, so that everything would be discovered, and her fiancà ¯Ã‚ ¿Ã‚ ½ would be put to justice. After Alesha's holiday had finished, she kept in touch with the other kids. Maybe the holiday wasn't so bad after all!

If You Read Nothing Else Today, Read This Report on Ftce English 6-12 Essay Samples

If You Read Nothing Else Today, Read This Report on Ftce English 6-12 Essay Samples As a consequence, it can be quite overwhelming to get ready for these certification exams. On-line study workshops are offered at distinct times during the year. The FTCE series comprises a wide-range of exams linked to specific educational topics in addition to exams linked to certain careers within the educational system. With an open-ended assignment, there's a much increased emphasis on working correctly rather than working quickly. This document also tells the quantity of candidates tested and provides the proportion of passing scores for each distinct exam. Remind the students there are lots of kinds of evidence. Focus your studies on this region. The precise FTCE exams that are needed as a way to turn into a certified educator within the Florida school system varies dependent on the specific sort of position that you're interested in pursuing. Such questions exist solely for the advantage of administrators and won't influence your general score. The secret to perfect gift giving is to regard the graduate. Enroll today and begin on your trip towards Florida teacher certification! The Good, the Bad and Ftce English 6-12 Essay Samples You would require a knife and fork and, well, that isn't how a burger is intended to be devoured. As a consequence, you get a fantastic deal of free time and completed homework. There are varieties of basketball courts but make certain you're likely to find the maximum excellent court for your kid. Attempt to establish a backyard court. Ftce English 6-12 Essay Samples: the Ultimate Convenience! You want to understand how to compose an effective essay as it is a typical foundation for a student's grade. Students have to compose essays based on the teacher's instructions or their preferred style in writing. They will be able to add them to their own vocabulary lists, and even see how the words are used in other videos. A students should work hard to provide a reminder of the principal flavors of the essay. Paragraph writing worksheets are ideal for third graders. Be sure to come up with FTCE focused essay writing skills however good of a writer you're. To compose an impressive short essay, especially during an examination, you should be in a position to hit the question and supply a straightforward answer while at the identical time observing the proper structure of an essay. There's quite a few essays completed by them. Your paragraphs do not connect one another's meaning and the whole thought of your essay may be incomprehensible. If you're able to observe patterns of words or phrases in your incorrect choices in addition to your correct choices, you will enhance your likelihood of passing the actual test. From time to time, the best method to learn and understand new information is by way of seeing and understanding work which is already completed. The content isn't a secret. There are lots of things you want to do in order to make certain you're having an effective study session. A good deal of folks feel overwhelmed with the idea of creating an eBook. There are a great deal of great choices there when you're searching for songs for in-class pursuits. This is a huge alternative for those students who have zero opportunity to do solid research or don't understand how to do it the correct way. My fear is really much gone. More so, it can lead to a fantastic deal of stress, frustration and disappointment. Because of this, you will need to concentrate on boosting your writing skills by your FTCE practice. That way it's possible to locate your strengths so that you may concentrate on your weak areas whenever you do use your time to study. Whispered Ftce English 6-12 Essay Samples Secrets There's no ideal solution on how best to compose an effective essay. 240Tutoring offers a money-back guarantee for people who purchase a subscription. Our study scheduling tool makes it possible to make an FTCE study schedule and keep it up. Please take a couple of minutes to complete our on-line survey regarding services you have gotten. Click the one which you like to look at the most. Your instruction was so clear and simple to follow. Don't forget that the FTCEs are intended to be revised. Then return and read it again.

Analysis Of Julius Caesar s Funeral Speeches - 2096 Words

One of the most arbitrary, but compelling bonds formed in society is that which is formed during communication involving an exchange of information. Almost all knowledge, behaviour, or emotion can be traced to, or is derived from some sort of network that connects a sender to a receiver. This relationship often provokes action as a result of how the information is conveyed by the informant. The aforementioned analogy applies inextricably to this bond in that the bias present in the delivery of information inclines the recipient to view the information similar to the sender, rather than impartially. Four devices in particular can be attributed to the persuasiveness of the bias in the information. When evaluating Julius Caesar s funeral speeches, this is especially pertinent. Antony was the most influential rhetorician because of his ability to exploit the crowd’s emotions surrounding the assassination of Caesar, and how he was able to effectively leverage his position as a clos e friend of Caesar; Brutus was more balanced and consistent in his use of rhetorical devices. While Brutus’s oration was convincing, it was undermined by Antony’s onslaught of examples which damaged Brutus’s credibility, and gave him a decisive authority over the crowd. The focal point of the contention of ethos was the honor of Brutus. Specifically, Antony challenged if Brutus was as virtuous in the intent behind the murder as he said. As such, the crowd was most impressionable to the speaker who was