titration

which instruments to be rinsed with water and solution and why

pipette and burette , ensure concentration stays the same and reduce dilution due to remaining distilled water

to avoid parallax error

1. read at eye level

2. ensure burette is vertical

3. place a white tile behind the reading

other important measures

1. read below the meniscus

2. use funnel to convert solution into burette and remove when solution starts

3. wash flask which you will be pouring pipette solution into with the solution

4. tap burette in case of air bubbles

5. final answer 0.10 diff , initial and final 0.05 diff

6. wear goggles

pipette bulb

1. Press A to evacuate air

2. attach S onto pipette and press it to bring solution up

3. Press E to eject solution

which instruments to rinse with water and why

conical flask , keep mols of solution consistent

why is conical flask better than beaker

smaller neck and less splashes , easy to swirl

what is present in conical flask at the endpoint

indicator ,salt , water

how does air bubbles affect final reading + how to remove

recorded volume is smaller than actual volume of liquid delivered , tap the edge of burette

methyl orange colour change

acid : colourless to red , endpoint distinct orange

alkali: colourless to yellow , endpoint pale orange

phenolapthelin colour change

acid : colourless to pink

alkali : pink to colourless

end point : pink

titration procedure/steps

1. Rinse burette, pipette twice with water + solution

2. Rinse conical flask , funnel twice with water

3. Rinse flask for pipette solution with solution

4. Transfer solution to burette using flask , ensure meniscus (bottom of it) hits 0

5. If there are air bubbles , tap it against empty flask

6. Transfer other solution using pipette (ensure have pipette bulb) into conical flask , add 2-3 drops of indicator

7. Start titrating and swirling , add small amounts , once there is a hint of colour change stop or go slower

8. record final readings to 0.10 cm³