Redox Titration: Things to review and note

1. Question

In s FeSO₄ vs KMnO₄ titration: which solution goes in the burette?

KMnO4
Fe2+
Fe3+
Mn2+

2. Question

How should the volume of KMnO₄ be read?

From the bottom of the meniscus
From the bottom of the meniscus
From the top of meniscus, 2dp, last digit is 5 or 0, eye level

3. Question

How should a volumetric pipette be used?

control level using pipette filler pump
bottom of the meniscus sits on the graduation line
using mouth, straight from the stock solution bottle
eye level, touch the last drop on the surface

4. Question

Which indicator is required for the Fe²⁺/MNO₄^– titration?

phenolphthalein
univeral indicator
methyl orange
none

5. Question

Indicator used in Iodine thiosulphate redox titration

Methyl orange
Phenolphthaleine
Does need an indicator
Starch

6. Question

When is starch added to a titration in an I₂/ S₂O₃^2- titration?

at the start before titration
halfway when it turns lighter brown
when it is pale yellow almost colourless
when it is colourless

7. Question

Why is it important to not add iodine at the start in an iodine-thiosulphate titration?

Insoluble complex forms meaning titre value is too high
Insoluble complex forms meaning no end point will be seen
Insoluble complex forms meaning titre value is too low
Insoluble complex forms meaning no blue-black colour is seen

8. Question

Starch has just been added to an iodine titration at stage:

a
b
c
d

9. Question

What is the sequence of colours in the iodine-thiosulphate titration?

brown to yellow to blue/black to colourless
brown to blue/black
yellow to blue/black to colourless
colourless to blue/black

10. Question

Which rows are required for a titration results table?

initial volume, final volume
final volume, initial volume
start volume, titre
final reading, initial reading, vol of titre

11. Question

How many decimal places should the burette readings be recorded to?

1
2
0
3

12. Question

What errors are in this titration table?

results are identical so too SUS
did not do 3 titrations
did not tick best titration results
final burette reading, not volume

13. Question

What is an error in this titration table?

no errors
Volume of Q labelled should indicate chemical
titration results are not close enough within +/- 0.20cm3
missing units for readings

14. Question

Concordant results mean…

titres are within O.20 cm3
titres are identical
titration resutls are within the teacher's bandmark
titres are within 0.01cm3