Tuesday, October 22, 2019

Lab on Aspirin Tablets Essays

Lab on Aspirin Tablets Essays Lab on Aspirin Tablets Essay Lab on Aspirin Tablets Essay This lab was basically about finding the percentage of acetylsalicylic acid in an aspirin tablet. First, the base was created, which was made out of 1. 00 g of NaOH and D-water. Then the buret was attached to the clamp on the ring stand and the base was poured into the buret. After that, one by one, an aspirin tablet was dropped into an Erlenmeyer flask filled with 50 mL of D-water so that it could become dissolved. After the tablet was completely dissolved, a few drops of phenol were added, and the base was added very slowly, changing the color of the mixture into a pink. The flask was to be swiveled around. This was done three times, trying to get the pink color to stay for at least two minutes. Materials: * D-water * Scale * Slop beaker * Erlenmeyer Flask x3 * Volumetric Flask * Ring Stand * Buret * Buret Clamp * Phenolphthalein * NaOH * Weighing boats * Aspirin Tablets x3 * Stirring Rod * Scoopula Purpose: The purpose of this lab was to find the percentage of acetylsalicylic acid in n aspirin tablet. Theory/Intro: Aspirin possesses a number of properties that make it the most recommended drug pretty often. It is an analgesic, which means that it is very effective in pain relief. Being an anti-inflammatory agent, it is also provides some relief from the swelling associated with arthritis and minor injuries. It also reduces fever because it is an antipyretic compound. More than 40 million poun ds of aspirin are produced in the U. S. every year. This rate breaks down to about 300 tablets per year for every woman, man, and child. However, repeated use may cause gastrointestinal bleeding, and large doses can provoke a host of reactions including vomiting, diarrhea, vertigo, and hallucinations. The average dose is approximately 0. 3-1 g, but single doses of 10-30 g can be deadly. The most important compound in the synthesis of aspirin, salicylic acid, is prepared from phenol by a process discovered over 100 years ago by a German chemist Hermann Kolbe. Also known as acetylsalicylic acid, aspirin has a chemical formula of C9H8O4. Aspirin is sold over the counter and comes in many different forms. You can have white tablets to chewing gum and rectal suppositories. Also available are coated, chewable, buffered and extended release forms. Over the counter medicines like Alka-Seltzer Original Effervescent Antacid Pain Reliever, contains aspirin for pain relief. Aspirin belongs to a group of drugs called salicylates. Aspirin isn’t so easy on the stomach because it is quickly absorbed into the bloodstream and provides quick and relatively long-lasting pain relief. Aspirin also reduces inflammation. Researchers believe these effects come about because aspirin blocks the production of pain-producing chemicals which are called prostaglandins. While it does relieve pain and reduce inflammation, it also lowers fever by acting on the part of the brain that regulates temperature. The brain then sends signals to the blood vessels to widen, which allow any heat to leave the body more effectively. Procedures: 1. Make 100 mL of 0. 20M NaOH solution. 2. Find mass of one tablet. 3. Dissolve tablet in flask using, 50mL of D-water. Use a stirring rod to assist in crushing and dissolving the tablet. There should be some powdery substances on the bottom of the flask, it’s the starches put in the tablets. 4. While one partner is dissolving the tablet the other one should be setting up the buret and stand. Place the clamp on the stand. Next wash the buret with a little D-water before placing the buret on the clamp. Next fill the buret with NaOH solution up to a place above the â€Å"O† marking on the buret. Open the buret, to allow some of the base to run into a slop beaker thus filling the tip. Make sure the level of the liquid is now below the zero mark. Record the reading after filling the tip. 5. Add several drops of the indicator, phenolphthalein, to the flask. 6. Slowly add the base while swirling the flask. Continue add base until a faint pink color stays in flask. Record the value from the buret. Add a few drops more and see if the color stays and changes. You do not want a dark purple color. Record the final value of base needed. 7. Repeat the process for two more tablets, for three in total. Refill the buret after each trial. Drawing Observations: 1. The aspirin tablets were white. 2. The aspirin tablets had a smooth texture. 3. The aspirin tablets were odorless. 4. The NaOH was a frosted white color. 5. The NaOH was odorless. 6. The base was a clear color; no powdery substances were left behind. . When the NaOH was put in D-water it dissolved thoroughly leaving nothing behind. 8. When the aspirin tablets were put in D-water they took a while to dissolve. 9. When the aspirin tablets were finally dissolved, powdery substances were left behind. 10. When the base was mixed with the dissolved aspirin tablets nothing happened. 11. When the drops of phenol were added, then the mixture turn ed pink. 12. At first, the base was added to quickly so it turned into a dark pink, almost purple. 13. After swiveling the mixture a few times it would lose its pink coloring and turn back into a clear color. 4. At the second try, the base turned into a medium pink color. 15. It stood pink for a longer period of time, approximately 1 minute. 16. The mixtures for all three trials were odorless. 17. At the last try, the base was a light pink color, and it stayed for two minutes. 18. When too much base was added to the phenol/ dissolved aspirin, the mixture would turn into a dark pink. 19. When the base was added in slowly, the pink color lasted a longer time. 20. The faster the base was added, the darker the mixture got, and the longer it took to return to its original clear color. Conclusion: One source of error could’ve been that the NaOH solution that was poured into the buret wasn’t at the zero mark. This could have affected the end results because if it wasn’t at the zero mark that means that we had more liquid then needed, so when the base was poured into the phenol/dissolved aspirin mixture the recordings weren’t accurate. That means that the calculations were thrown off because the wrong amount was used. Another source of error could’ve been that when the 1. 00 g of NaOH was measured it wasn’t exact. The scale is very sensitive and maybe breathing could’ve affected the outcome. This affects our results because now there isn’t as much NaOH as there should be in the base, which could cause a difference when the aspirin and phenol are mixed with base. The color could’ve maybe stayed for longer. The last source of error could’ve been that the base was poured in too quickly from the buret, causing the color change to be off.

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