• University of California, Davis

• CHE 2b

Post-Lab Data Summary Note : some questions will display a variable like "nCount" or "SyInput" instead of an actual number in the data summary. Q# Question Text 4) Data Entry - No Scoring Please enter the precise mass in grams of the sodium carbonate sample in each of your three trials. You should enter the mass to the thousandth of a gram, e.g. 0.178 g. Your Answer: 0.143 No Points Possible Your Answer: 0.128 No Points Possible Your Answer: 0.128 No Points Possible 5) Data Entry - No Scoring Please enter the volume of water used to dissolve each of the samples of sodium carbonate. You should enter the volume to a hundredth of a milliliter, e.g. 30.04 mL Your Answer: 30.01 No Points Possible Your Answer: 30.03 No Points Possible Your Answer: 30 No Points Possible 7) Data Entry - No Scoring Please enter the volume of HCl required to reach the first equivalence point in your titration of sodium carbonate for each of the three trials. Be sure to enter the volume of HCl in the corresponding sequence with the mass of Na2CO3 for the trials. That is, enter the volume of HCl required for each respective mass of Na2CO3 on the same line as that mass. You should enter the volume to the nearest 0.02 mL, e.g. 10.04 mL. Your Answer: 6.48 No Points Possible Your Answer: 5.98 No Points Possible Your Answer: 5.99 No Points Possible 8) Data Entry - No Scoring Using your titration curve, determine the pH that corresponds with the volume of HCl at the first equivalence point in your titration of Na2CO3 and enter the observed value for each of the three trials. Enter the pH to three significant figures, e.g. 7.78. Your Answer: 7.98 No Points Possible Your Answer: 7.99 No Points Possible Your Answer: 8 No Points Possible 9) Data Entry - No Scoring Please enter the volume of HCl required to reach the SECOND equivalence point in your titration of sodium carbonate for each of the three trials. Be sure to enter the volume of HCl in the correspond