complete table
LAB 11
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TABLE 1: |
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PART 1 |
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BEAKER |
PH RANGE |
COLOR CHANGE(INITAIL;FINAL) |
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#1 BLUE |
10.49:5.82 |
BLUE;CLEAR LIGHT YELLOW |
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#2 TURMERIC |
10.49:3.99 |
ORANGE;LIGHT BLUISH YELLOW |
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#3 ORANGE |
10.41:3.21 |
ORANGE;LIGHT RED |
PART 2
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ML CITRIC ACID NEEDED FOR NUETRALIZATION |
NEUTRALIZATION PH |
MOLES OF CITRIC ACID USED |
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1.5 |
-1.34 |
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Table 2: citric acid – sudsy ammonic titration data indicator used |
1.What is the pH of the solution at the equivalence point as shown by your titration curve/derivative plot (Part 2)?
2.Which indicator shows a color change at about the same pH as this equivalence point?
3.Explain, in detail, then justify with evidence, your choice for your indicator in Part 3.
4.How did the mL of titrant needed to reach the endpointusing the indicator you chose (Part 3) compare with the mL of titrant needed to reach the equivalencepoint (Part 2)? What does this say about these two methods? Is one a better means of monitoring a titration than the other? Why or why not?
5.If you were standardizing a solution of NaOH like you did in a previous lab, which method of titration monitoring is better, do you think—using a pH probe to make a titration curve, or monitoring the end of the titration via an indicator color change? Why?
6.What are at least two possible sources of error in your experiment, and how could one account for these sources in future experimental runs? Discus