A student performs this experiment but forgets to remove air bubbles from the NaOH buret valve. (a) Would the measured volume of NaOH added in the back-titration be incorrectly high or low? (b) How would this error affect the results of the experiment? Question 2 options:   (a) incorrectly low (b) % CaCO3 incorrectly high   (a) incorrectly high (b) % CaCO3 incorrectly high   (a) incorrectly low (b) % CaCO3 incorrectly low   (a) incorrectly high (b) % CaCO3 incorrectly low

(4. What effect would the following errors have on the final value of Ka determined from this experiment? a. The pH meter was calibrated incorrectly and the actual pH was 6.4 when the meter read 7.0. The student recorded and used the meter readings. b. After measuring the 10.00 mL of acid, the student added 80 mL of distilled water instead of 75 mL.

At the beginning of the titration your burette reading was 2.75 mL and at the end of the titration the reading was 28.27 mL. What is the volume of titrant used in this titration? Your Answer: Answer

EXPERIMENT 10 PRE-LABORATORY QUESTIONS STANDARDIZATION OF A SODIUM HYDROXIDE SOLUTION NAME DATE 1. What is the purpose of this experiment? 2. A sample of KHP has a mass of 2.345 g is used for a titration, how many moles of KHP is this sample? 3. How many moles of NaOH would be needed to reach the endpoint of this titration with sample of KHP from the previous question? 4. If the initial volume of the NaOH in the burette was 0.50 mL and the final volume is shown to the right, what is the volume of NaOH used in this titration? 19 5. What is the concentration of the NaOH solution used in this titration? EXPERIMENT 10 155

Name: Postlab Questions: 1. A student was performing the test for chloride in his unknown. When he added the five drops of HNO3, he observed bubbles forming (effervescence) in his unknown. Was chloride present in his unknown? How do you know? 2. A student added barium chloride to her unknown and immediately witnessed the formation of a precipitate. She concluded that this white precipitate indicated the presence of chloride ion in her unknown. Is she correct? How do you know? 3. A student has two unlabeled bottles of solution. One contains PO4³¯ and the other SO,?". How can this student identify which is which? Page 6 of 6

I'm stuck all those questions need help

Thank you! Data included in pictures! No hand drawn graphs!! Determine the equivalence point and the endpoint of the sudsy ammonia/citric acid reaction by graphing the titration data (pH vs volume citric acid) from Table 3: Titration of Sudsy Ammonia with 0.25 M Citric Acid Data with the Chosen Indicator. Draw a green arrow (use ‘Insert Shape’ feature to do this once you have copied your graph from Excel) on your graph indicating the data point that represents your equivalence point. Draw a blue arrow (use ‘Insert Shape’ feature to do this once you have copied your graph from Excel) on your graph indicating the data point that represents your endpoint. Use a graphing software to create the x-y scatter plot showing the pH of the experimental solution as a function of the volume of citric acid (the titrant) added for the titration data in Question 9. On your graph, the x-axis should be the volume of citric acid added (mL), and the y-axis should be the pH of the experimental…

rial Number Total Volume of Titrant Added (mL) Post Lab Questions 34.7 b) 34.7 Burette contains 0.70M of KOH and 100mL of Mystery CH3COOH 34.7 All part of same question. 1. Using data collected from the titration, determine the concentration of the assigned unknown solution. a) Using your answer from question 1, determine the pH of the unknown acetic acid solution BEFORE the titration began (i.e., when no base has been added) if Ka of acetic acid is 1.8x10-5. Determine the pH of the solution AT EQUIVALENCE POINT of the titration.

Using the average volume of NaOH as well as its concentration, calculate the average # of moles of NaOH used in your titrations.