Acids & Bases

Question 1

How to get data to make pH against volume graph

Answer 1

Pipette 25cm3 of base/alkali into conical flask
Record pH with pH meter
Add acid from burette in small increments
Swirl flask & record pH
Repeat until 40cm3 of acid added
Use smaller increments of acid near end point

*Known concentration in burette

Question 2

How to choose most suitable indicator

Answer 2

Repeat titration with each indicator
Select indicator that changes rapidly at the steepest part of curve

Question 3

Reason for anomaly in pH curve

Answer 3

Didn’t swirl mixture properly

Question 4

How to calibrate pH meter

Answer 4

Use solutions with know pH
Adjust metre when necessary