Metals are oxidized into metal cations as they lose electrons and their charge i
ID: 1065790 • Letter: M
Question
Metals are oxidized into metal cations as they lose electrons and their charge increases. Thus metals are reducing agents. Metal cations are reduced to metal elements (solids except for Hg) as they gain electrons and their charge is reduced to zero. Thus metal cations are oxidizing agents. Answer the following questions about solid Zn, Cu, Pb, Mg, and Ag and their corresponding aqueous ions. Make sure to include (s) or (aq). bullet Which is easiest to oxidize? bullet Which is hardest to oxidize? bullet Which is easiest to reduce? bullet Which is hardest to reduce? bullet Which is the best reducing agent? bullet Which is the best oxidizing agent?Explanation / Answer
Arrange the elements in increasing order of standard reduction potentials:
Mg < Zn < Pb < Cu < Ag (the standard reduction potential values can be obtained from tables).
The lower the value of the standard reduction potential, the more reducing is the metal, i.e, it itself gets oxidized and reduces the other element.
a) Mg has the lowest reduction potential and hence easiest to oxidise (ans).
b) Ag has the highest reduction potential and hence most difficult to oxidise (ans).
c) Ag is the easiest to reduce since it has the highest reduction potential (ans).
d) Mg2+ is the hardest to reduce (ans).
e) Mg2+ is the best reducing agent (ans)
f) Ag+ is the best oxidizing agent (ans).