a technique called titration in which a solution with a known concentration is slowly added to a
solution of unknown concentration until the solution is neutralized.
The neutralization is
indicated by a change in color of the titrated solution.
Through titration we can find the exact
molarity of a solution.
This is called standardization and it is important in a plethora of
In order to do any calculation that deals with concentration, we must standardize.
In this lab, we will first seek to standardize a solution of potassium permanganate using solid
samples of FAS (iron(II) ammonium sulfate hexahydrate) via titration.
The chemical reaction
for this is: MnO
(aq) + 5 Fe
(aq) + 8 H
(aq) → Mn
(aq) + 5 Fe
(aq) + 4 H
once the molarity of KMnO
is found, we will use that to calculate the mass percentage of
hydrogen peroxide in bleach by titration once again.
The final reaction is:
(aq) + 5 H
(aq) + 6H
(aq) → 2 Mn
(aq) + 5O
(g) + 8H
The buret for the experiment was initially rinsed out with boiled distilled water three
times to make sure that there was no residue left from previous experiments. Then the buret was
primed by having KMnO
run through the entire volume of the buret twice. For trial one, 0.251
grams of FAS was measured out and placed in 250 mL beaker. 2.0 mL of H
was mixed into
the beaker along with 10 mL of boiled distilled water. Then two drops of H
was added. The
contents were then stirred till the entire contents seemed to be dissolved. The H
was of a 9
molar concentration and the H
was of a 6 molar concentration.
was then added via