Brandon Meas Block: B Day 4 Lab day 1 5/12/17 Lab day 2 5/23/17 Lab Day 3 6/2/17 Lab 9: Acids and Bases Purpose: The purpose of the lab is to calculate the concentration of a known acid. Using the data collected from this lab, you will calculate the molarity of the acid. Introduction: In chemistry, concentration is the amount of a substance in a given volume of space. Concentration is also the ratio of solute in a solution to either solvent or total …show more content…
An indicator is something that changes color at a specific pH value or in the presence of a particular substance and can be used to monitor acidity or the progress of a reaction. You will know you are done with your Titration when the solution completely is indicated a certain color for a long period of time. The amount of OH and H3O at this point will be equal at pH 7. The mathematical formula used for titration calculations is Macid x Vacid = Mbase x Vbase Procedure: During preparation for this lab, measure out 2 to 3 mL of NaOH. Obtain a waste beaker and place it under the burette and make sure the stopcock is closed. Measure out 20 mL of Acetic Acid and pour it into an Erlenmeyer Flask. Add 2 drops of a chemical reaction indicator, Phenolphthalein, to the Acetic Acid. Remove the waste beaker from under the burette and replace it with the Erlenmeyer Flask. From the NaOH in the Burette, add it to the acid milliliter by milliliter. The solution should gradually turn pink. When the solution starts to stay a pink color for a longer period of time, decrease the rate of the dropping of NaOH. Be sure not to overshoot the amount of NaOH. Record the final volume of the NaOH when the solution turns completely pink. Before clean up, put the waste beaker under the burette and drain the remaining NaOH from the burette. Dump the waste into a bigger waste beaker your instructor provides. Pour the Acetic Acid down the drain. Repeat the procedure one more time, and if there is more time, repeat a 3rd time. Repeat clean up
== Volume of NaOH used is recorded below: Trial (cm3) 1st time (cm3) Initial burette reading 3.55 18.4 Final burette reading 22.8 36 Titre 19.25 17.6 pH Chloroethanoic acid 3.0 Dichloroethanoic acid 2.2 Ethanoic acid 4.6 pH of chloroethanoic acid and dichloroethanoic acid is given by the teacher. Calculation: = ==
collect any gas given off). A timer was needed to time how long the experiment took. The conical flask was then filled with 100cm3 of acid.
The purpose of this lab is to understand the concepts of pH and buffers and how to make a buffer in the laboratory. Also, how to perform the titration process and identify the values of pKa, equivalence point, and the unknown buffer based on the titration process.
Next began adding the bleach to the petri dishes using pipettes. Each petri dish was given a different percentage of contaminant. Again, I set the timer for 5 minutes then counted the number of live brine
This procedure was conducted a total of three times. For each one of the trials the color change and calculations were recorded. The moles of hydrochloric acid neutralized by the unknown sample were found by subtracting the moles of sodium hydroxide (which was back titrated) , from the initial moles of hydrochloric acid. The moles of hydrochloric acid neutralized was then dived by the mass of pre weighed sample to give us the amount of moles of hydrochloric acid neutralized per gram of the unknown
The 50 mL beaker was filled with 50 mL of sodium hydroxide. The sodium hydroxide was poured into the buret, it was ensured that the buret read zero. The buret was placed in the buret holder and the Erlenmeyer flask was placed to help adjust the height of the buret.
middle of paper ... ... error to my experimental result, I will get the value of 63.27. Final experimental result = experimental value + the overall apparatus error = 62.37 + 0.9 = 63.27 % difference between experimental Mr and value of likeliest value = (62 / 63.27) × 100% = 100% − 97.99% = 2.01% 4.3 Conclusion From the titration process I found the molarity of the sodium hydroxide solution and the relative formula mass of the unknown acid. With further calculations I identified the correct formula of the acid.
The aim of the experiment is to titrate a strong acid and a weak acid with a primary standard
The materials I used in this lab were red cabbage juice, red and blue litmus paper, measuring cups, a paper towel, distilled water, vinegar, apple cider vinegar, laundry detergent, lime juice, a pH chart, and finally, a dropper. The first step in this lab report is to take one drop of cabbage juice from the measuring cup and put it into the other measuring cups, or the other 5 liquids, and mix the solution together. Next, using the pH chart, decide the color of the solution and record the results. Third, dip the red and blue litmus paper into all of the measuring cups and place them on a paper towel to determine whether each substance is an acid or base using the pH scale. And finally, record all your results in the data chart putting the number each solution is under “pH”, and putting acidic, basic, or neutral under “effect on litmus
The purpose of this lab was to understand the difference between a strong acid and a weak acid and how that affects its titration curve. We were also asked to estimate the ionization constant of a weak base with the data we collected. The first step of the experiment was to put 50 drops of acetic acid into a small beaker. We then recorded the pH values after 0,10,20,30,40,45,50,55,60, 70,80,90, and 100 drops of NaOH was put in the beaker. The pH was recorded by using pH paper and dipping it into the solution at each increment and then comparing it to the color chart.
To describe the relative concentrations of different solutions the terms hypotonic, hypertonic and isotonic are used. A hypotonic solution is one that has a higher concentration of water and a lower solute concentration, while a hypertonic solution has a lower concentration of water and a higher concentration of solute. Both these solution represent unequal concentration of molecules on either side of the membrane and will result in a net flow of water by osmosis to equalize the side’s concentrations. Correspondingly, two solutions are considered to be isotonic when equal concentrations of solute and water exist on both sides of the
The pH meter needed to be calibrated before the titration, and this was done by using coloured standards of pH 4.0, 7.0 and 10.0. The NaOH used within this practical was measured out in pellet form, and the amount needed was 0.4g of 0.1M NaOH. The NaOH was then dissolved into 100ml of distilled water by using a magnetic stir bar and a magnetic stirrer, which mixed the solution for around 120 seconds. After the NaOH had been dissolved, 25ml of 0.1M CH3COOH was measured into a measuring cylinder and was then transferred into a 100ml beaker. This was also placed onto the magnetic stirrer and a clean magnetic stirrer bar was then added to avoid any contamination before the NaOH had been added. The calibrated pH meter was then added to the CH3COOH and the initial pH reading was then taken, which was 2.8pH. By using a p200 pipette, 500µl aliquots of NaOH were then added to the CH3COOH solution, and 30 seconds were left between each aliquot to ensure the pH meter registered the changed pH. The pH of the solution was then recorded on a graph of pH vs volume of 0.1M NaOH added. After this, another 500µl (0.5ml) of NaOH was added and recorded until 40ml had been added (Thorne, A.
Moles HCl .0006575mol Concentration of HCl .06575 M b. Computer Data Graph: See Attached. c. 23Drops From Buret = 1mL. VI. Mathematics a. Stoichiometry Molarity = Mole(L) /
Pour 1.40g of NaOH into florence flask and add 350ml distilled water, then swirl it and invert flask five times with parafilm on the top of it. Next, obtained a vial of KHP from the instructor, and poured about 0.408g into three different Erlenmeyer flasks by measuring with analytical balance. Then, fill up about 25ml of distilled water, add 3 drops of phenolphthalein into it and mix them well with a glass rod. Label all solutions to prevent mixing them up. Before the titration began, the buret should be rinsed with NaOH solution and recorded the initial buret reading.
In this experiment we are trying to identify an unknown acid or base and its concentration by using the method of titration. The pKa values and the titration curve help aid in identifying of the unknown. In our case we had a base as our unknown (analyte). The use of a certain amount of sodium hydroxide and hydrochloric acid will be used to titrate the unknown solution that is given. This is the tirant. We used hydrochloric acid as our titrant. We achieved a pH of 5.56 at an end point of 10 milliliters. The unknown’s concentration was around 0.098 M at pka(s) of 6 and 7. The sodium hydroxide and hydrochloric acid are called titrant and it is contained in a container called burette. The unknown solution is held in an erlenmeyer flask. The purpose of the experiment is to measure the weak acid and base by neutrilizing it and determining the unknown acid by titration.