Accuracy and Precision in Volumetric Analysis (Leaving Cert Chemistry): Flashcards
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Practise the cards
15 cards from this deck
What is accuracy?
What is accuracy?
How close a measurement is to the true value
What is precision?
What is precision?
How close repeated measurements are to each other
High accuracy & high precision pattern
High accuracy & high precision pattern
Shots near centre & grouped together
Low accuracy & high precision pattern
Low accuracy & high precision pattern
Shots grouped together but away from centre
Why does accuracy matter in volumetric analysis?
Why does accuracy matter in volumetric analysis?
Ensures correct concentration values
Why does precision matter in experiments?
Why does precision matter in experiments?
Indicates reliability & consistency of technique
Equipment precaution for accuracy
Equipment precaution for accuracy
Use properly calibrated equipment
How to prevent parallax errors
How to prevent parallax errors
Take readings at eye level
How to rinse burettes & pipettes correctly
How to rinse burettes & pipettes correctly
Rinse with the solution they will contain, not water
Endpoint control technique
Endpoint control technique
Add solution drop-by-drop near endpoint
Common cause of accuracy errors
Common cause of accuracy errors
Incorrectly calibrated equipment
Common cause of precision errors
Common cause of precision errors
Inconsistent technique between measurements
23.5, 23.6, 23.7 vs true 23.0
23.5, 23.6, 23.7 vs true 23.0
Good precision, poor accuracy
Effect of not rinsing burette with solution
Effect of not rinsing burette with solution
Water dilutes solution, affecting accuracy
Where are accuracy & precision crucial industrially?
Where are accuracy & precision crucial industrially?
Pharmaceutical manufacturing quality control