Acid-Base Titration
Safety
- Use of a pipette filler
- Use of gloves where appropriate
Accuracy
Indicator Phenolphthalein Methyl
-rinse apparatus with the appropriate solution Orange
Acid Colourless Red
-add solution drop-wise near the end point
Neutral Colourless Orange
-swirl the flask and the flask with deionised water Alkaline Pink Yellow
Titrations Strong Base Strong
-read the burette at the bottom of the meniscus
Acid
Reliability
-Repeat
-concordant readings should be obtained within 0.1cm3 of each other
Carrying out a dilution of a solution
Pipette 25.0 cm3 of the original solution into a vol. flask
Add deionised water to the flask until it is just below the line
Add water using a disposable pipette slowly until the bottom of the meniscus is on the line
Stopper the flask and invert to mix
Dilution factor: found by dividing new volume by volume of original solution
Preparing a solution from a mass of solid/ volume of a liquid
-weight out mass of solid in weighing boat, or accurate vol. of liquid and dissolve in a
suitable vol. of deionised water in a beaker, stirring w. a glass rod. Then rinse equipment
into beaker w. deionised water.
-Dissolve solid/liquid in deionised water. Remove glass rod and rinse into beaker
-Place a glass funnel over a vol. flask. Pour contents of beaker in using a glass rod.
-Rinse glass rod and funnel into beaker
-Remove the funnel, add deionised water until it nearly reaches the line
-Use a disposable pipette to add water the bottom of the meniscus
-Stopper the flask and invert to mix
Safety
- Use of a pipette filler
- Use of gloves where appropriate
Accuracy
Indicator Phenolphthalein Methyl
-rinse apparatus with the appropriate solution Orange
Acid Colourless Red
-add solution drop-wise near the end point
Neutral Colourless Orange
-swirl the flask and the flask with deionised water Alkaline Pink Yellow
Titrations Strong Base Strong
-read the burette at the bottom of the meniscus
Acid
Reliability
-Repeat
-concordant readings should be obtained within 0.1cm3 of each other
Carrying out a dilution of a solution
Pipette 25.0 cm3 of the original solution into a vol. flask
Add deionised water to the flask until it is just below the line
Add water using a disposable pipette slowly until the bottom of the meniscus is on the line
Stopper the flask and invert to mix
Dilution factor: found by dividing new volume by volume of original solution
Preparing a solution from a mass of solid/ volume of a liquid
-weight out mass of solid in weighing boat, or accurate vol. of liquid and dissolve in a
suitable vol. of deionised water in a beaker, stirring w. a glass rod. Then rinse equipment
into beaker w. deionised water.
-Dissolve solid/liquid in deionised water. Remove glass rod and rinse into beaker
-Place a glass funnel over a vol. flask. Pour contents of beaker in using a glass rod.
-Rinse glass rod and funnel into beaker
-Remove the funnel, add deionised water until it nearly reaches the line
-Use a disposable pipette to add water the bottom of the meniscus
-Stopper the flask and invert to mix
