Chapter 5 Acid-Base Volumetric Analysis Flashcards
Define acid-base titration
It is an analytical procedure involving a reaction between an acid solution and a base solution
Define standard solution
a solution with a precisely known concentration
What is the purpose of a titration?
Purpose is to determine the concentration of the acid or base in the solution of unknown concentration
Define aliquot
The measured solution that comes out of the pipette
Define titre
the measured solution that is in the burette
Define equivalence point
It is the theoretical point in the titrations (when neither nor base remains)
What is used to to see the equivalence point of a titration?
An acid-base indicator
Define end point of a titration
The point where the indicator changes colour signalling the equivalence as occurred.
What two points are very close approximations in titration?
The end point and the equivalence point
Define primary standard
One of the accurately known concentration that can be used in a titration to find the concentration of other reagents.
How is a primary standard prepared?
It is prepared by carefully weighing the sample of the primary standard, dissolving it in distilled water and then making the solution up to a precise volume in a volumetric flask.
What features must a primary standard have?
It must:
-Be able to be obtained in a very pure form consistent with its chemical formula
-Be sufficiently stable so that on exposure to air, it doesn’t readily change its water content or react with other gases in the air
-Have a relatively high molar mass
These features allow the moles of a primary standard to be precisely calculated from its accurately measured mass and molar mass
Define secondary standard
A solution whose concentration is determined by titration against a primary standard
