MHS Chemistry
Titration Contest

Assignment Question
What volume of "base" is required to exactly neutralize a small volume (10.0 - 15.0 mL) of "acid"?

Hints & Notes

  1. The reaction is    HCl(aq) + NaOH(aq) --> NaCl(aq) + HOH(l)
  2. Use a couple of drops of phenolphthalein indicator to see when the reaction is complete.  Aim for the lightest pink that you are sure is pink.
  3. Before starting, develop a data table to record all of your information.
  4. Examine the burets used to dispense the acid and the base.  Burets are labeled to measure volume dispensed, so when they are full, they read "0.0" (because they haven't dispensed anything).   Be sure to record data from these properly.


  1. After determining the answer to the "assignment question," use the given concentration of base to determine the concentration of acid for each trial.
  2. Determine the average concentration of the acid for your group's trials.
  3. Determine the average deviation of your results.  Average Deviation is the average of how different each meaurement is from the average.  Don't use negative numbers in this calculation.  Also, re-read the previous two sentences many times until they make sense: it's not a difficult calculation.

What To Pass In
One lab report, amazingly perfect, for each group.  The report must be on one piece of paper (front and back is OK).  If it's on two sheets of paper it's a "rough draft" and will be returned for re-writing.

  1. Title stuff (the usual).
  2. Purpose.  Hint: it's NOT the assignment question.
  3. Data/Results Table.  Each trial gets it's own column, decimals lined up, proper sig figs, labels, names -- all the good stuff from any data table.  For ease of reading, you may include the concentration of acid (result) as the last line in the data table.
  4. Sample Calculation.  Clear and complete calculation for the first trial.
  5. Overall Results: Clearly show the average concentration of the acid from all of your group's trials.  Also, calculate the average deviation and report that.

Bonus Points

  1. TEN points for the group whose average concentration is closest to the average concentration obtained from all groups in all chem classes.
  2. FIVE points for the group in each class whose average is closest to the class average.  This can't be the same group as gets the ten point bonus, and no bonuspoints will be awarded for second place.
  3. FIVE points for the group with the smallest average deviation of all classes.
  4. THREE points for the group in each class with the smallest average deviation, except the group that gets the second five point bonus.

Although it is wonderful news that you can work together as groups to pass this lab in, you can be sure that there will be a short and fairly straightforward quiz about this lab.  Yes, it will be open notes, but remember: you need to understand what you write, take credit for, and read, in order to be successful (and not just in chemistry).

[Titration Contest Score Sheet][MHS Chemistry Page]