REQUIRED PRACTICAL: NEUTRALISATION (TITRATION)

EQUIPMENT

PIPPETTE - to accurately measure a certain volume of acid/alkali
CONICAL FLASK - to contain liquid from pippette
BURETTE - to add alkali/acid to conical flask
WHITE TILE - to place conical flask on

METHOD

With pippette add fixed volume of alkali to conical flask
Add drops of indicator
Put flask on a white tile
Fill burette with acid
Note starting volume
Slowly add acid from burette to the alkali swirling to mix
When the indicator changes colour stop adding the acid Note final volume
Calculate how much acid you added
Repeat until you get two concordant results
Find mean volume required

WHY DO WE SWIRL?

to evenly distribute the indicator added

WHY DO WE PLACE ON WHITE TILE

so we can easily see the colour change

THREE TYPES OF INDICATOR

LITMUS (red in acid, blue in alkali)
PHENOLPHTALIEN (colourless in acid, pink in alkali)
METHYL ORANGE (red in acid, yellow in alkaline)

When should phenolphatalien and methyl orange be used

When the acid and alkali are strong