i) A reacts spontaneously with 1 mol/L BNO3, 1 mol/L D(NO3)2 and dilute sulfuric acid. A does not react with 1 mol/L C(NO3)2.
ii) B does not react spontaneously with any of the 1 mol/L solutions above or with dilute sulfuric acid.
iii) C reacts spontaneously with dilute sulfuric acid and with 1 mol/L solutions of all the other metallic salts.
iv) D reacts spontaneously with 1 mol/L BNO3. It does not react with dilute sulfuric acid.
a) Use the observations and arrange the following five reduction half-cell reactions in order, the one with the largest positive reduction potential listed first.
A2+ + 2e- ? A(s)
B+ + e- ? B(s)
C2+ + 2e- ? C(s)
D2+ + 2e- ? D(s)
2H+ + 2e- ? H2(g)
b) Which metal is the best reducing agent?
c) Which ion is the best oxidizing agent?
I don't understand these observations at all..