Describe the preparation of potassium permanganate. How does
acidified KMnO4 solution react with :
(i) SO2
(ii) Oxalic acid
Write ionic equations for these reactions.
Answers
ELECTROCHEMICAL FUNDAMENTS
As you know, copper ions are related to a Transition's Metal.
This relation is based on an electrochemical trendy obeying to an electromotive force leading this phenomenon.
W. H. Nernst collected the "Electrochemical potential at Standard Conditions" that is he dipped a metallic copper rod in a 1 M copper ion's aqueous solution : this system is a "First Electrode Type" and it may form a Voltaic Pile when it is connected to a S.H.E. Electrode. The latter is formed by a platinum's sponge dipped in a 1 M hydrochloric acid's aqueous solution receiving a gas-stream of hydrogen bubbles flowing at 1 atm.
Nernst measured a "E.M.F." like 0.34 V ; he assigned 0.00 V to S.H.E.'s system, hence the Copper's Electrode receive the Standard Electrical Potential as E° = +0.34 V, meaning that Copper's Electrode is MORE NOBLE than S.H.E.'s ones.
You may change this experiment if you dipp the metallic copper rod in a 1 M POTASSIUM IODIDE's aqueous solution instead copper ion's one. You may measure an "E.M.F." like 0.19 V ; Nernst assigned 0.00 V to S.H.E.'s Electrode, hence the NEW COPPER's ELECTRODE have a Standard Electrical Potential as E° = -0.19 V, meaning the NEW Electrode results LEAST NOBLE than S.H.E.'s one.