Question

Your ticket will appear here once you na ve correctly ans w ered an or ше реао quesuon. Prelab for Experiment 6- Titration of an Unknown Acid In this prelab, answers to questions l and 2 should be reported toateastisennoantngurs Scientific notation format 2.34E 4. The 'E' must be capitalized." The prelab questions mirror those that you will be doing at the end of the experiment. Bring your work for this prelab assignment to lab and you will have a much easier time completing the Data Analysis Sheet at the end of the experiment. You will need the answer to question II during the experiment Stydent information Enter your name (first and last) and the last 4 digits of your student number. Number: Name L. At the endpoint of a titration, the color of the solution should be O faint pink pink colorles:s bright pink IL. We will calculate the amount of acid to use in each titration. Assume that you are using 0.0512 M NaOH ag good volume of NaOH(aq) to use per titration is 15 ml. From this molarity and volume, the moles of NaOiH can be calculated. Since the unknown acid is monoprotic, this also equals the number of moles of acid to use. A typical molar mass for an unknown acid in this experiment is 380 g/mol. Using this molar mass, calculate the (in grams) of unknown acid you should use per titration. Since we have heen estimating values, round your answer to two significant figures. Hint I. At the endpoint of a titration, the color of the solution should be faint pink pink O colorless O bright pink II. We will calculate the amount of acid to use in each titration. Assume that you are using 0.0512 M NaOH(aq). A good volume of NaOH(aq) to use per titration is 15 mL. From this molarity and volume, the moles of NaOH can be calculated. Since the unknown acid is monoprotic, this also equals the number of moles of acid to use. A typical molar mass for an unknown acid in this experiment is 380 g/mol. Using this molar mass, calculate the mass (in grams) of unknown acid you should use per titration. Since we have heen estimating values round your annier to hio siguificant figures. Hint 1. Suppose that 12.51 mL of 0.0512 M NaOH were required to titrate a sample of unknown acid. How many moles of NaOH were used? mol 2. Assuming that the unknown acid sample in question I had a mass of 0.177 g, what is the molar mass of the unknown acid? g/mol License Points possible: 5 Unlimited attempts

Answer 1

1. 0.000640 moles

2. 276 gm per mole

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