Answer Happy

Part 1. Absorbance & Calibration Curve 05 A calibration curve of Albance values CS Absorbance vs. Concentration of FeSON 2 03 0.5 bsorbance 0.3 03 o -0.19 0.00005 0.0001 0.0001 Concentration of 6.500 A. The absorbance values of two unknown FeSCN? solutions are recorded below Absorbancs Unknown #1 453 0.453 Unknown W2215 3765.6x1 = 11gxion us 3793.c. -1.89 10m B. Determine the concentration of FeSCN* (concentration is in Molarity) for each of the unknown absorbance values by "estimating" from the prepared graph (show this on the graph) Concentration of FeSCN2 Unknown #1 (2.5pts) Unknown # 2 (2.5pts)

Part 2. Hydrolysis of Salts (15 pts) A. The pH of 5M NCHO, has been med de recorded below pH of NaC,H,O, 8.24 B. 1. Show the Dissociation of the NaCH3O2 (4 pts) 2. Show the hydrolysis equation (4 pts) C. In 2-3 sentences explain whether the measured pH supports the hydrolysis equation. (7 pts)

Part 3. Buffers (15 pts) The pH of solutions A & B have been measured and recorded below. a. Measured pH of each solution Solution A PH 4.74 Solution B pH = 6.50 px a DH -5 1-32 Xia x 10 b. Calculate the [H30] in each solution Solution A [H3O*]- (3 pts) Solution B [H307- Show your calculation for [H30* A1 0 ka=104.74 (3 pts) B c. Determine which solution (A or B) is a buffer solution using the measured pH values above as well as the following information. Clearly indicate whether Solution A or Solution B is a buffer AND a reason for your conclusion. (7pts) Three drops of 6M HCl were added to each solution (Solution A & Solution B). The pH was measured and recorded. Solution A pH = 4.62 (after 3 drops of M HCl was added) Solution B pH = 1.32 (after 3 drops of 6M HCl was added)

Part 5. Freezing Point Depression (10 pta) The following temperature-time data were obtained for a solution made by dissolving 2.1379 of. camphor in 28.101g of paradichlorobenzene. The freezing point of paradichlorobenzene is 53.1°C and its Ke-7.1°C/m. Cooling Curve for Camphor-Paradichlorobenzene Mixture 60 Temperature (°C) 59 58 57 56 55 54 53 52 51 50 49 48 47 o 2 Time (min) a. Using the graph above, determine the freezing point of the camphor-paradichlorobenzene mixture. Indicate on the graph how you determined the freezing point. (3pts) Freezing point of mixture: b. Determine the molar mass of camphor, assuming, that it is a nonelectrolyte. Show you work below. (7pts)