experiment 9: determination of iron permanganometry

Question 1

A titration which involves reduction and oxidation reaction

Answer 1

Redox titration

Question 2

Example of a redox titration

Answer 2

Permanganometry

Question 3

What are the strong oxidizing agents used in Permanganometry

Answer 3

Permanganates

Question 4

what happens when permanganates is used as a titrant to oxidize ferrous ion in acidic conditions

Answer 4

the purple color of the permanganate ion disappears upon contact with the ferrous-containing sample

Question 5

balanced net equation of permanganates is used as a titrant to oxidize ferrous ion

Answer 5

MnO4 + 5Fe + 8H <—-> Mn+ 5Fe + 4H2O

Question 6

how to know when the titration is ending and what is the endpoint of titration

Answer 6

titration ends upon the appearance of a faint pink color which persists for 30 seconds
all of the ferrous ion have been consumed and converted to ferric ion

Question 7

what must be done before using the potassium permanganate solution too oxidize all of the containments present in the reagent and water

Answer 7

potassium permanganate solution must boil

Question 8

protect the standard solution from?

Answer 8

the standard solution must be protected from light and must be restandardized if solids are detected upon storage

Question 9

what is the net equation of potassium permanganate solution standardized against a standard sodium oxalate

Answer 9

5C2O4+ 2MnO4 + 16H <—-> 2Mn + 10CO2 + 8H2O

Question 10

why does the sodium oxalate solution needs to be heated

Answer 10

as it reacts with permanganate very slowly at room temp

Question 11

reagents

Answer 11

pre-dried standard Na2C2O4 distilled water
FeSO4.7H2O
KMnO4
0.90 M H2SO4
2M H3PO4

Question 12

weigh how many KMnO4

Answer 12

0.64 to 0.65 g

Question 13

how long must u boil the KMnO4 solution

Answer 13

1hr

Question 14

weigh how many grams of Na2C2O4

Answer 14

0.10 to 0.11 g

Question 15

add how many mL of 0.90 M H2SO4

Answer 15

100 mL

Question 16

in the standardization of KMnO4 solution, heat the solution to how many degree Celsius

Answer 16

70-80

Question 17

when titrating with the KMnO4 solution while heating until the appearance of a persistent faint pink color, the temperature should not drop ____

Answer 17

below 60 degree celcius

Question 18

in determination of iron in an unknown sample, add how many mL of unknown sample by using what equipment

Answer 18

25 mL of unknown sample
volumetric sample

Question 19

in determination of iron in an unknown sample, add how many mL of distilled water and how many mL of 2 M H3PO4

Answer 19

50 mL distilled water
12 mL of 2 M H3PO4

Question 20

where should excess permanganate solution be disposed

Answer 20

in an organic waste container

Question 21

equipment used

Answer 21

stove