Three trails were carried out with the final results having a 0.10 mL difference of titrant. The average titrant was 17.57 mL. The purpose of this investigation was to determine to molar concentration of acetic acid in vinegar. The experiment showed the amount of ethanoic acid present in each 20 mL aliquot of diluted vinegar was 0.087835 mol/L and the concentration of ethanoic acid in the undiluted vinegar was 0.87835 mol/L.
The reactions that occurred during the experiment were neutralization reactions, meaning that the moles of acid equaled the moles of base at the end of the experiment as shown by the ratio in the equation, 1:1.This reaction involved acetic acid which is a weak acid and NaOH which is a strong base. Phenolphthalein was used as an indicator which changes color from colorless to pink. This color change demonstrates the end point was reached and the reaction was complete. Phenolphthalein changes color at a pH range of 8.0-10.0. Therefore it can be expected that the final concentration will be in around 0.8M to 1.0M which happened as the calculations showed.
…show more content…
Also the titrant may drip onto the sides of the conical flask and may not react with the solution in the conical flask. It is important to swirl the conical flask constantly to ensure that the contents are mixed evenly. Another important factor is to add in the titrant in small drops to insure the results are precise. Instead of using tap water, deionised water was used for washing the apparatus. This is because deionized water will not affect the results as it has a neutral
the replicate shows the same trend as the first experiment. I used a measuring cylinder and a beaker to measure out the amounts of water; however these did not seem to affect the quality of my results. To increase the accuracy of my results I could have perhaps used a burette. Even though I did the best I could to keep the experiment accurate, I did. some places there were mistakes that unintentionally occurred.
Repeat for each trial. Rinse volumetric pipette with vinegar and drain into the waste beaker. Weigh and record the mass of each 200mL beaker. Add 10.00mL of vinegar into each beaker and weigh them and record their again. Add 50mL of de-ionized water to the beakers and place them under the drop counter on top of a stir plate, submerging the pH meter into the solution. Place the stir bar into the beaker and carefully turn on the stir plate so that the stir bar spins without splashing or hitting the sides of the beaker or the pH
For acid into water, the pH level dropped drastically, from 6 to 3. For base into water, the pH increased from 6 to 12. During the buffer experiments, the pH level stayed the same during the whole experiment for acid and base. It stayed at a pH of 12, hence the name “Buffer
Firstly, an amount of 40.90 g of NaCl was weighed using electronic balance (Adventurer™, Ohaus) and later was placed in a 500 ml beaker. Then, 6.05 g of Tris base, followed by 10.00 g of CTAB and 3.70 g of EDTA were added into the beaker. After that, 400 ml of sterilized distilled water, sdH2O was poured into the beaker to dissolve the substances. Then, the solution was stirred using the magnetic stirrer until the solution become crystal clear for about 3 hours on a hotplate stirrer (Lab Tech® LMS-1003). After the solution become clear, it was cool down to room temperature. Later, the solution was poured into 500 ml sterilized bottle. The bottle then was fully wrapped with aluminium foil to avoid from light. Next, 1 mL of 2-mercaptoethanol-β-mercapto was added into fully covered bottle. Lastly, the volume of the solution in the bottle was added with sdH2O until it reaches 500 ml. The bottle was labelled accordingly and was stored on chemical working bench.
· Rinse out mixture in flask and leave water running to get rid of the
Apparatus: * 1 measuring cylinder * 1 test tube * 1 stop clock * A large gelatine cube containing indicator and NaOH * Hydrochloric acid ranging from 1-3 molars * A scalpel Diagram: Method: * Take the large gelatine cube and cut into 15 equal pieces * Place on piece of the cube into the test tube * Measure out 10mls of HCl in the measuring cylinder * Pour the HCl into the test tube with the gelatine cube and start the clock * Time how long it takes for the pink colour inside the gelatine cube to completely disappear * You will also notice that the cube dissolves slightly * Record your results and repeat this same process 3 times for each molar of acid: § 1 molar § 1.5 molar § 2 molar
Base being Baking Soda, or Sodium Bicarbonate, and the acid being Vinegar, or Acetic Acid for a control. I measured 10 ml. of Vinegar, dumped that into a two inch high glass jar, and wrote down the pH level. Then I measured o...
This would give us an extra measure of accuracy each time. Another way to improve the experiment and to produce consistent readings was to used distilled water. This is because the distilled water contains no impurities and therefore no hardness in water.
From looking at the results I can conclude that when the pH was 3 and
Compared to the 0.5 M hydrochloric acid that was less concentrated, the more concentrated 2 M hydrochloric acid c...
The sample was subjected to steam distillation as illustrated in Figure 1. A total of 50ml of distillate was collected while recording the temperature for every 5.0 ml of distillate. The distillate was transferred into a 250ml Erlenmeyer flask and 3.0 g of NaCl was added. The flask was cooled and the content was transferred into a 250-ml separatory funnel. Then 25.0ml of hexane was added and the mixture was shaken for 5 minutes with occasional venting. The aqueous layer was discarded and the organic layer was left inside. About 25.0ml of 10% NaOH was then added and the mixture was shaken as before. The aqueous layer was collected and then cooled in an ice bath. It was then acidified with enough 6.00 M HCl while the pH is being monitored with red litmus paper. Another 25.0 ml of hexane was added and the mixture was shaken as before. The hexane extract was saved and a small amount of anhydrous sodium sulfate was added. The mixture was then swirled for a couple of minutes then filtered. A small amount of the final extracted was tested separately with 1% FeCl3 and Bayer’s reagent.
The reason for this is that separate drops were entered one at a time and their volume was computed in order to add to the total of the. However, due to the fact of adding drops one at a time. time became an issue while completing the experiment. One titration took nearly 30 minutes to complete flawlessly.
vii. This would allow the determination of the percentage of citric acid in the lemon juice specifically, rather than the total acidity. The results of this could have been compared to those of the titration, and the contribution of citric acid to the overall initial acidity could have been determined.
Initially, before any NaOH is added, the pH of H2C2O4 .2H2O is low because it contains mainly H3O+. The starting pH will, however, be higher for a weak acid, like H2C2O4 .2H2O, than for a strong acid. As NaOH is added, H3O+ is slowly used by OH- because of dissociation of NaOH. The analyte remains acidic but the pH starts to increase as more NaOH is added.
For this experiment we used titration to standardize the exact concentration of NaOH. Titration is the process of carefully adding one solution from a buret to another substance in a flask until all of the substance in the flask has reacted. Standardizing is the process of determining a solutions concentration. When a solution has been standardized it is referred to as a standard solution. To know when a solution is at its end point an indicator is added to acidic solution. An indicator is an organic dye that is added to an acidic solution. The indicator is one color is in the acidic solution and another color in the basic solutions. An end point occurs when the organic dye changes colors to indicate that the reaction is over (Lab Guide pg. 141).