Sagedamini esinevad korrosioonid
solution of potassium hexacyanoferrate(III); zinc-plated iron sheet; tin-plated iron sheet; iron
paper clips; solid NaCl; urotropin.
Equipment
Test tubes, small beaker (50 cm3), centrifuge tube.
Experiments
1. Making of a galvanic pair
1.1. Place a zinc granule on the bottom of the centrifuge tube and pour solution of
hydrochloric acid on top. Write down the equation of reaction which occurs. Which
compound is the oxidant, which is the reductant?
Zn+2 HCl ZnCl 2 + H 2
-¿ H 2
Oxidant is H: +¿+2 e ¿
2 H¿
2+ ¿
¿
Reductant is Zn: -¿ Zn
Zn 2 e ¿
Next, insert the copper wire into the same solution in the centrifuge tube, ensuring that it will
not touch the zinc granule
annaabi.ee 
