Titrations Flashcards
All 6 cards in this deck
What is a titration used to find?
The volumes of acid and alkali solutions that react exactly with each other.
Name an indicator used in an acid–alkali titration and give its colour change as acid is added to alkali.
Phenolphthalein: pink → colourless (or methyl orange: yellow → red).
Why is universal indicator not used in a titration?
It changes through a range of colours, so it does not give a sharp end point.
Which pieces of apparatus are used to measure the alkali and the acid in a titration?
A (volumetric) pipette measures a fixed volume of alkali into the conical flask; a burette holds and measures the acid added.
Give two reasons why a burette is used for the acid in a titration.
It can add the acid in small increments (dropwise) and can measure variable volumes accurately — more accurate than a measuring cylinder.
What are concordant titres?
Repeat titres that agree within 0.10 cm of each other; only these are used to calculate the mean titre.