100 mL water sample was subjected to DO analysis using the Winkler method. The initial reading of the titrant (0.025 M Na2SO3) in the buret was 2.51 mL. The endpoint was obtained and the final reading was 7.07 mL. A blank was also titrated and 0.75 mL of the titrant was consumed. Compute for the amount of DO (mg/L) in the sample.

12. Collect a sample of lake water; a) 100 mL titrate with 0.05N HCl to HCO3 eq.pt. and we need to add 0.5 mL of acid solution. What is the CO32 ALK as M and mg CaCO3/L? b) 100 mL titrate with 0.03N NaOH to CO3 eq.pt. and we need to add 0.6 mL of base solution. What is the OH ALK as M and mg CaCO3/L? c) What is the CT and pH value?

Let HA represent a weak acid. A 27.5 mL sample of 0.20 M HA was titrated with 0.25 M NaOH. The following data were collected during the titration. Volume NaOH added (mL) 5.50 11.00 16.50 22.00 pH 5.28 5.88 6.48 9.98 What is the K, for HA? 5.2 x 10-6 None of these 1.0 x 10-10 3.3 x 10-7 1.3 x 10-6

Prepare another 5 cuvettes with different concentration of Pi using the stock 1mM Pi, 0.5mM PNPP solution (in water) and 0.2M Tris-HCl, pH=8.00. For this part, the concentration of PNPP will remain constant at 0.150mM. Fill the table below (before coming to lab) and use it to prepare your cuvettes. The completed table must be in your pre-lab. Your blank for each reaction is the PNPP mixed with Tris-HCL and Pi. Again, prepare one cuvette at the time to minimize exposure of the PNPP to the air. You can prepare your next cuvette while your previous one is being read.  previous one is being read.  Final [Pi]uM Volume of 1mM Pi Final [PNPP] mM Volume of 0.5mM PNPP Volume of 0.2M Tris-HCl (uL) Volume of enzyme (uL) Total Volume (uL) 0   0.150     100 1500 3.33   0.150     100 1500 20   0.150     100 1500 50   0.150     100 1500 100   0.150     100 1500

What is the pH at 110.00 mL of titrant in the titration of 50.00 mL of 0.400 M B (a generic base with Kp = (7.58x10^-9)) with 0.200 M HNO3? Enter your answer in scientific notation with 3 sig figs. Do not include any units in your answer. Do not round any intermediate calculations. Note: Your answer is assumed to be reduced to the highest power possible. Your Answer: x10 Answer

A sample containing NaOH only was titrated with standard 0.1280 M HCl, requiring 25.45 mL to reach a point beyond the endpoint. To compensate for this, the sample was back titrated with 0.1030 M NaOH solution, requiring 0.35 mL to reach the desired endpoint. If 9.00 mL of the sample was used for titration, calculate % (w/v) NaOH in the sample

How do I determine the volume of NaOH delivered and the molar it’s of the standard NaOH?

A different titration experiment using a 0.122M standardized NaOH solution to titrate a 26.48 mL solution with an unknown Molarity concentration (M) of sulfuric acid (H2SO4) gave the following molarities for 3 trials.    Initial Burette Reading (mL) Final Burette Reading (mL) Delivered vol (mL) Acid Concentration (M) Trial 1       0.0345 Trial 2       0.0334 Trial 3       0.0381 From the 3 trials, determine the average Molarity concentration of the H2SO4 to 3 significant digits. Don't include a unit.

10.00mL of 0.10M acetic acid were collected in an Erlenmeyer flask, and then diluted to 100mL with distilled water. After that, two drops of indicator were added. Then, the buret was filled with 0.100M NaOH. The titration was started by slowly adding NaOH to acetic acid. (Note: Ignore the volume of the indicator added, as the volume is tiny compared to 100mL.) What is the pH of the solution in the Erlenmeyer flask after adding 10.00mL of 0.100M NaOH?   Question 3 options:   7.22   6.9   8.35   7.00

a) Compare between equivalence point and endpoint. Distinguish which point comes first. b) James performed an acid base titration experiment. A 25 mL sample containing HCl was transferred to Erlenmeyer flask using volumetric pipette. HCl sample was titrated against standardized 0.5010 M NaOH. An average titre volume of 24.35 mL was reported. Suggest a suitable pH indicator for James to be used in this experiment. Predict the initial concentration of the HCl. c) Alan and friends wish to sketch a weak acid strong base titration curve. Before they can do so, they need some data points. In a case where 50 mL of 0.20 M CH3COOH (Ka = 1.80 x 10-5 ) was titrated with 0.05 M NaOH, deduce the pH after addition of different volumes of NaOH. (i) 0 mL NAOH (ii) 100 mL NaOH (iii) 200 mL NaOH