Volumetric Analysis and titrations Flashcards
What is a standard solution?
A solution with known (accurate) concentration
What is volumetric analysis?
Analysis of solutions. It is a technique used to determine the amount of an analyze in a solution and it can be used for acid base reactions, redox reactions and precipitate titrations
Steps to do volumetric analysis
- Write out an equation
- Find the number of moles of what you know or can find the moles of.
- Ratio (what you want : what you got)
- Find the moles of the unknown.
- Find the concentration of the substance that is desired.
What is a primary standard?
A solution that can be directly used in a titration that is solid, cheap, of high molecular weight and doesn’t change it’s composition over time.
What is a secondary standard?
Must have the concentration determined by the primary standard, not solid, expensive, of low molecular weight, changes composition over time.
What is an indicator?
A substance that changes color and is mainly used in an acid/base titration. They change color with pH and they are selected on the basis of the equivalence point.
A weak acid titrated against a strong base requires an indicator that changes color between _______. So the best selection would be ________
9 and 10
Phenolphthalein
A strong acid titrated against a weak base requires an indicator that changes between _______. Therefore ______ is the best indicator for this titration
3 and 4
Methyl orange
Titration of a strong acid against a strong base requires the indicator that changes around pH of ______. Therefore ________ is the best indicator for this titration
Bromothymol blue
What is an equivalence point?
The point at which the reactants are exactly equivalent in terms of moles
What is an end point?
The point at which the indicator changes color. If carefully chosen it will match the equivalence point.
Concordant results are reached by getting ____ titres within ____ of each other.
3
0.05mL
