In a 250 mL beaker, pour 100 mL of a potassium
permanganate aqueous solution (10 - 2 mol. L - 1),
then add 50 mL of a 5% sodium
hydroxide aqueous solution.
Slowly pour the content of the beaker into a funnel covered
with filter paper, containing 20 grams of manganese
dioxide (IV). The filtrate is then collected into a
250 mL Erlenmeyer flask.
CAUTION : the 5% sodium
hydroxide aqueous solution must be manipulated wearing
goves and safety goggles.
