Chem oxidizing agent

所謂既oxidizing agent 同reducing agent係相對既
Na 可以係一隻 strong reducing agent, 你都可以話佢係一隻weak oxidizing agent
至於點解NO2 係oxidizing agent,只不過佢咁岩遇到一隻比佢oxidizied 既reactant 姐
呢d野係相對既~咩名只不過係睇情況叫
希望有高人解釋得再清楚d

2012-03-13 02:24:43 補充：
thx土扁更正呀,
你可以參考下各隻agent 既emf value, 再了解下redox reaction!

2012-03-13 02:26:43 補充：
Fe 2+ 都係一個好好既例子

In rare cases, alkali metals can have negative O.N.
Say, [Na(2,2,2-crypt)]^(+) Na^(-) contains both "normal" sodium ion (complexed) and sodide ions. This kind of compounds are not very stable, but at least can transiently exist in room conditions.

2012-03-13 07:23:44 補充：
In that case, Na can be a (very weak) oxidizing agent.

The oxidation number (O.N.) of N in NO2 is +4. NO2 can be an oxidzing agent when it is reduced to NO (O.N. of N = +2), N2 (O.N. of N = 0) or NH3 (O.N. of N = -3). NO2 can also be a reducing agent when it is oxidized to HNO3 (O.N. of N = +5).

2012-03-13 01:51:39 補充：
Na can never be an oxidizing agent, because Na attains the lowest oxidation number (0).

The fact is : Na is a very strong reducing agent (to convert to Na^+), and thus Na^+ is a very weak reducing agent (to convert to Na).