Arrange the following metals in the order of their decreasing standard electrode potential: $Mg, K, Ba, Ca$.

Which metal among the following has the strongest tendency to undergo oxidation?

$(i)$ Copper metal dissolves in $1 \ M$ silver nitrate solution and crystals of silver metal get deposited.
$(ii)$ Silver metal does not react with $1 \ M$ zinc nitrate solution.
$(iii)$ Zinc metal dissolves in $1 \ M$ copper sulphate solution and copper metal gets deposited.
Hence,the order of decreasing strength of the three metals as reducing agents will be:

Assertion : Copper reacts with $HCl$ and liberates hydrogen.
Reason : Hydrogen is present above $Cu$ in the reactivity series.

What is the oxidation and reduction potential of standard hydrogen electrode?

The $E^{\circ}_{cell}$ of $Cu_{(s)} | Cu^{2+}_{(1M)} || Ag^{+}_{(1M)} | Ag_{(s)}$ is $0.647 \ V$. Calculate the $E^{\circ}_{Ag}$ if $E^{\circ}_{Cu}$ is $0.153 \ V$. (in $V$)