C the solution well past the equivalence point

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(c) the solution well past the equivalence point Explain your predictions. HINT: First write a balanced reaction. Remember that BaSO 4 is insoluble.
Penn State CHEM 113 Section B. Acid–Base Equilibria and Indicator Dyes Pre-lab data collection and observations. Complete before lab. Instructor adds 1 drop of Bromocresol green (acid-base indicator) into 3 wells in a 1x12 strip. Then adding 1 drop of 0.010 M HCl into the first well to observe change. Turns yellow = acid. Then add 1 drop 0.01M NaOH to 3 rd well and observe color change. Turns bright blue = base. Second well is left as a control. Section C. Determination of the K a Values of Weak Acid Indicators Pre-lab data collection and observations. Complete before lab. Use 1x10 well strip to observe reactions between a variety of buffers (pH values 1-12 with weak acid indicators. 1) Add 1 drop of methyl orange to each of the 12 wells, then add 1 drop of each buffer 1 – 12 in their corresponding well 1 – 12 and observe color change.
2) Add 1 drop of Bromocresol Green to each of the 12 wells, then add 1 drop of each buffer 1 – 12 in their corresponding well 1 – 12 and observe color change.
3) Add 1 drop of Bromothymol Blue to each of the 12 wells, then add 1 drop of each buffer 1 – 12 in their corresponding well 1 – 12 and observe color change.
4) Add 1 drop of Phenolphthalein Indicator to each of the 12 wells, then add 1 drop of each buffer 1 – 12 in their corresponding well 1 – 12 and observe color change.
Question 3: What is the color of the HIn form of bromocresol green?
Question 4: What is the color of the In form of bromocresol green?
Question 5: Look at your bromocresol green results. What is the color when you have equal amounts of HIn and In–? Does this make sense?
Penn State CHEM 113 Question 6: Based on your lab experiments, report (a) pK a , (b) K a , and (c) the pH transition range for each of the four acid-base indicators that you used. Also, show the pH transition range for each indicator using Figure 14.3 found following this question. There is an example of how to do this on page 14-32 of your lab manual.

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