Experiment 4 Name Potentiometric Analysis of Acid in Soft Drinks: Cola vs. Uncola Purpose Calculations A. Standardization of NaOH Mean conc. NaOH solution: M Standard deviation: M Relative standard deviation (%RSD): % B. Data for titration of cola and uncola with NaOH Using Excel or a similar program, make a table with the following columns: Vol. NaOH Added pH V2 - V1 pH2 − pH (V1+V2)/2 pH2 - pH₁ V2 - V1 C. Results Cola: pH of soda after boiling: Volume NaOH required to reach first end point: ± ml; pH: Volume NaOH required to reach second end point: ± ml; pH: H3PO4 concentration: H2PO4 concentration: M %RSD: M %RSD: Uncola: pH of soda after boiling: Volume NaOH required to reach the end point: ± _ml; pH: _ Citric acid concentration: ± M %RSD: Include all information from the Calculations/Questions section as well as sample calculations; answer all questions. Check your calculations carefully! Don't forget to include copies of your lab notebook pages for this experiment. Latest Volume pH d1 d2 (mL) 123 (pH/vol) (d1/vol) 0 2.07 -0.007 0.079 0.4 2.06 0.023 0.087 0.9 2.08 0070 0.089 4 1.3 2.13 0.110 0.057 5 1.5 2.15 0.103 0.022 6 10- 1.9 2.19 0.115 0.039 7 2.2 2.23 0.132 0.057 8 2.5 2.27 0.150 0.074 9 2.9 2.34 0.179 0.117 10 3.3 2.41 0.239 0.157 11 3.6 2.50 0.311 0.086 12 3.8 2.58 0.272 0.124 13 4.4 2.69 0 364 0.275 14 4.6 2.86 0.552 0.198 15 4.9 3.01 0.474 0.029 16 5.3 3.18 0.505 0.153 17 5.7 3.38 0.652 0.086 18 5.9 3.61 0.570 -0.074 19 6.4 3.78 0.531 0.100 20 6.7 3.99 0.679 0.231 21 7 4.23 0.689 0.257 22 7.4 4.44 0.817 0.279 23 7.6 4.71 0 983 -0.553 24 7.8 4.90 0.525 -0.567 pH d1 (pH/vol) d2 (d1/vol) 5- 25 8.3 5.04 0.435 0.019 26 8.6 5.18 0.655 0.187 27 8.9 5.49 0.633 -0.344 28 9.2 5.59 0.388 -0.523 29 9.5 5.70 0 262 -0.265 pH 8.06 Acid-Base Titration 0 5 10 15 20 -0 Volume (mL) 25

I dont know if I’m doing it right

X ch b Answered: Determine the pH du X + agage.com/static/nb/u/evo/index.html?deploymentid=55750823468596024212874980&eISBN=9781305657571&snapshop=30540668d-155276463... 2 req 2 req 2 req 2 req 2 req R MindTap-Cengage Learning X Back F4 shown below. Design a buffer that has a pH of 7.19 using one of the weak base/conjugate acid systems Weak Base CH3NH2 C6H1503N C5H5N $1 5 6. Prepare Buffers by Direct Addition: This is group attempt 1 of 5 Si grams weak base How many grams of the bromide salt of the conjugate acid must be combined with how many grams of the weak base, to produce 1.00 L of a buffer that is 1.00 M in the weak base? grams bromide salt of conjugate acid = 96 T F5 Kb 4.2×10-4 5.9x10-7 STE Conjugate Acid Ka CH3NH3 2.4×10-11 C6H1503NH+ 1.7×10-8 1.5x10-9 CsH5NH+ 6.7x10-6 F6 6 = Y X + F7 & 7 + Autosaved at 10:38 PM W F8 8 X F9 019 ( pka 10.62 7.77 5.17 9 F10 ☀- ) F11 0 @ F12 Regenerate Group (4) @ 1 Insert Next 10:38 11/3/2 PrtSc

▪ True or false: the internal standard behaves chemically just like the analyte, and it is not found in the sample(it is added) ▪ True or false: In analysis of blood alcohols, lead is a much better IS than n-propanol

A titration was done to determine the concentration of a sample of HCl. The volume of the acid sample used in each titration trial was 10.00 mL. The following data also was collected: a. What was the average volume of Ca(OH)2 used? b. Calculate the concentration of the HCl sample.

A student performed three aqueous layer titrations in Part 1 and they reported the following measurements: Final Burette Reading Initial Burette Reading Volume of Aqueous Aliquot Final Burette Reading Initial Burette Reading Volume of Sodium Thiosulfate Determination #1 16.33 mL 6.50 mL 9.83 m 31.98 mL 0.76 mL 31.22 mL Determination #2 Determination #3 26.76 mL 16.33 mL 10.43 mL 33.62 mL 0.88 mL 32.74 mL 36.95 mL 26.76 mL 10.19 mL 32.22 mL 0.41 mL 31.81 mL Which determinations were the student's 'best two'? Calculate the percent difference for the 'best two' and show the complete calculation. Note that the concentration of standard sodium thiosulfate, which the student used, is unknown.

How are you supposed to answer this question if no values are given besides the Kb of the possible analytes?

Procedure: Mix 0.01M KMNO4 and 2 drops of 6M H2SO4 with several drops of 1.0M K2C2O4. Observation: A slight color peach begins to appear.   5K2C2O4(aq) + 2KMnO4(aq)+ 8H2SO4(aq) → 2MnSO4(aq) + 10CO2(aq) + 6K2SO4(aq) + 8H2O(l)   Has oxidation and reduction occurred? If oxidation and reduction has occurred? If oxidation and reduction has occurred define the change in oxidation numbers for the following atoms and define what is undergoing oxidation and reduction:   Mn[ ? ] → Mn[ ? ]   C[ ? ] → C[ ? ]

BUFFER CAPACITY EXPERIMENT Part 1: Preparation and pH Meter Calibration Prepare 50 mL of 0.5 M acetic acid from a concentrated stock. Prepare 50 mL of 0.5 M sodium hydroxide from a solid. Part 2: Buffer Capacity Transfer 20 mL of 0.5 M acetic acid (Ka is 1.75*10-5), stir at a slow setting and measure the pH reading is stabilized. Add 1.0 mL of 0.5 M NaOH and measure the pH. Continue adding 0.5 M NaOH in 0.5 - 1.0 mL increments until a major spike in pH occurs. After the spike, add another two 0.5 – 1.0 mL increments of 0.5 M NaOH. Create a pH vs. Volume graph to determine the range of the buffer’s capacity. Compare the actual data (nonstandard conditions) with the theoretical data under standard conditions. I NEED HELP WITH CALCULATIONS AN SMALL RESULT INTERPRETATION DESCRIPTION PLEASE  TO UNDERSTAND WHAT I DID AND WHY THANKS

Need help with 6a-6e