Question

A concentration of lead nitrate in water can be stored in
A.An iron vessel
B.A copper vessel
C.A zinc vessel
D.A magnesium vessel

Answer 1

Higher the value of reduction potential of an element can displace the element having low value of reduction potential . To get the solution we have to understand the electrochemical series.
Complete answer:
-To get the solution of above mentioned question we have to first understand about the electrode, electrode potential and electrochemical series.
-Electrode: an electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit. They are used to provide current through nonmetal objects to alter them in numerous ways.
-There are two types of electrode, cathode and anodes. Cathode attracts the positively charged action. Anode attracts negatively charged anions.
-Electrode potential: electrode potential is the electromotive force of a galvanic cell built from a standard reference electrode and another electrode to be characterized.
-Electrochemical series: it is referred to as activity series is a list that describe the arrangement of elements in order of their increasing electrode potential value .the series has been established by measuring the potential of various electrode versus standard hydrogen electrode .in series, all reduction potential are given on hydrogen scale whose is taken as zero.
-The standard reduction potential of an element is a measure of the tendency of that element to get reduced. The element which has greater reduction potential gets reduced easily .The element having high negative value of electrode potential than other can displace the less electrode potential element.
Now, $P{b^{ + 2}} + 2{e^ - } \to Pb$ having standard potential $E_{cell}^ \circ = - 0.13V$
And, $F{e^{ + 2}} + 2{e^ - } \to Fe$ having standard potential $E_{cell}^ \circ = - 0.41V$

$Z{n^{ + 2}} + 2{e^ - } \to Zn$ Having standard potential $E_{cell}^ \circ = - 0.76V$

$M{g^{ + 2}} + 2{e^ - } \to Mg$Having standard potential $E_{cell}^ \circ = - 2.38V$
$C{u^{ + 2}} + 2{e^ - } \to Cu$ Having standard potential $E_{cell}^ \circ = 0.16V$
Hence from the above reactions, we can clearly get that apart from $Cu$ having reduction electrode potential less than $Ni$ cannot displace lead nitrate, that is it can be stored in copper vessels.

Hence, option B is the correct answer for this question.

Note:
The reference electrode is the standard hydrogen electrode. It is defined to have a potential of zero volt. Electrode potential appears at the interface between an electrode and electrolyte due to the transfer of charged species across the interface.
-The cathode and anode have a certain electrode potential independently and the difference between them is the cell potential:
${E^ \circ }_{cell} = {E^ \circ }_{cathode} - {E^ \circ }_{anode}$