$Zn_{(s)} | Zn^{2+}_{(aq)} || Cu^{2+}_{(aq)} | Cu_{(s)}$ is

What is the reaction occurring at the anode in a $CH_4 - O_2$ fuel cell?

The charge over the anode in a galvanic cell is

At $298 \ K$,the standard electrode potentials of $Cu^{2+}/Cu$,$Zn^{2+}/Zn$,$Fe^{2+}/Fe$ and $Ag^{+}/Ag$ are $0.34 \ V$,$-0.76 \ V$,$-0.44 \ V$ and $0.80 \ V$,respectively. On the basis of standard electrode potential,predict which of the following reactions cannot occur?

Which of the following metals will precipitate copper from copper sulphate solution?

Saturated solution of $KNO_3$ is used to make a 'salt-bridge' because: