CHM110H5 Lecture Notes - Lecture 1: Titration, Equivalence Point, Sodium Hydroxide
Document Summary
The three chloro substituted derivatives of acetic acid are mono-, di-, and tri-chloroacetic acids. Conventional techniques can be used to measure only the proton attached to the oxygen atom. The other hydrogens attached to the carbon are not acidic enough. These acids each have a different k a value for the carboxylic acid proton. Ha + naoh a- + na+ + h2o. The experiment began by calibrating the solution at ph 4. When the solution reached ph 5-6, it was recalibrated with ph 7 buffer and at about ph 9, it was recalibrated again with ph10 buffer. After calibration, 25ml of the unknown acid was added into a 100ml beaker and titrated with the naoh solution provided. A magnetic stirring bar was used to keep the solution thoroughly mixed. Titration began by titrating 3ml in approximately 0. 25ml increments and then approximately 1 ml increments were used until the ph starts to rise noticeably and finally 1 drop increments were used.
