RP 9 - Investigating pH changes Flashcards
What is an acid?
A proton donor
What is a base?
A proton acceptor
What is an alkali?
A base that dissolves in water
Why are acid base indicators used?
To detect when a reaction reaches completion/becomes neutral usually by the presence of a colour change
Why does a pH probe need to be calibrated?
So that the pH values of each pH reading are accurate
What is accuracy?
The more accurate the data the closer is to the actual value
How can you investigate a weak acid pH changes upon condition of strong base?
1) Add 2 cm³ of sodium hydroxide from a burette to ethanolic acid in a conical flask.
2) Continue adding 2 cm³ of sodium hydroxide measuring the pH each time.
Why is it important to stir the resulting solution?
So all acid and bass is thoroughly mixed so the pH doesn’t significantly vary throughout the solution as this would give an inaccurate reading
How would you analyse this data?
Plot graph of measured pH values against volume of NaOH solution added
