Question

Determination of Ka and Identification of an Unknown Weak Acid Post-lab Question 1. Suppose that a student performing this experiment mistakenly calibrated the pH meter using pH 8 buffer instead of pH 7 buffer. As a result of this error, all of the student's pH readings were too low. a) Would this error have affected the calculated molar mass of the unknown acid? Briefly explain. b) Would this error have affected the experimentally determined pKa of the unknown acid? Briefly explain. 2. Was the percent difference between your unknown and the proposed compound greater for the molar mass or for the Ka? What does this mean about the accuracy of your pH measurement compared to your volume measurement? 3. diluted to a volume of 1.00 L. Ka for hypochlorous acid, HCIO, =2.96 x 10 (a) Calculate K of the sodium hypochlorite solution. prepared by adding 0.200 mol of Sodium Hypochlorite (NaCIO) to water an A solution was (b) What is the pH if 20.0 mL of 1.00 M HCl solution were added to 100.0 mL sample of the original sodium hypochlorite solution?

Answer 1

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