8.13 Identify the substance oxidised reduced, oxidising agent and reducing agent for each of the following reactions:

(a) 2AgBr (s) + C6H6O2(aq) 2Ag(s) + 2HBr (aq) + C6H4O2(aq)

(b) HCHO(l) + 2[Ag (NH3)2]+(aq) + 3OH(aq) 2Ag(s) + HCOO(aq) + 4NH3(aq) + 2H2O(l)

(c) HCHO (l) + 2 Cu2+(aq) + 5 OH(aq) Cu2O(s) + HCOO(aq) + 3H2O(l)

(d) N2H4(l) + 2H2O2(l) N2(g) + 4H2O(l)

(e) Pb(s) + PbO2(s) + 2H2SO4(aq) 2PbSO4(s) + 2H2O(l)


(a) Oxidised substance C6H6O2

Reduced substance  AgBr

Oxidising agent  AgBr

(b) Oxidised substance  HCHO

Reduced substance AgNH32+

Oxidising agent AgNH32+

Reducing agent  HCHO

(c) Oxidised substance  HCHO

Reduced substance Cu2+

Oxidising agent Cu2+

Reducing agent   HCHO

(d) Oxidised substance N2H4

Reduced substance H2O2

Oxidising agent H2O2

Reducing agent N2H4

(e) Oxidised substance Pb

Reduced substance PbO2

Oxidising agent PbO2

Reducing agent Pb