Answer to Question #125814 in General Chemistry for Tara

Question

In one part of a galvanic cell, the graphite rod is immersed in the acidic solution of K2Cr2O7 and Cr (NO3) 3, and in the other part, a castle rod is inserted in the solution of Sn (NO3) 2 and the KNO3 salt bridge connects them. Has done. The tin electrode is negative relative to graphite. Specify the cell diagram and the equilibrium equation for the reaction and display of the cell

Answer 1

The galvanic cell is an electrochemical cell that converts chemical reactions into electrical energy. It is made up of different parts which includes,

1. Two electrodes the anode where oxidation occurs and the cathode where reduction occurs.
2. An external circuit where electrons flows between the electrodes.
3. The half-cells for both reduction and oxidation reactions and they are separated into sections.
4. A salt bridge which connects cathode and anode and it helps to keep electrical neutrality in the internal circuit.

At the anode, the following oxidation reaction occurs,

$Sn^{2+}_{(aq)}\ \ +2e^-\to \ \ Sn_{(s)}$

At cathode, the following reduction reaction occurs,

$6e^-\ +14H^+_{(aq)}\ \ +Cr_2O^{-2}_7(aq)\ \to\ Cr^{3+}_{(aq)}\ +7H_2O_{(l)}$

The overall reaction,

$Sn^{(2+)}_{(aq)}\ \ +Cr_2O^{2-}_7(aq)+ 14H^+_{(aq)} \ \ \to\ Sn_{(s)}\ \ +Cr^{3+}_{(aq)}+7H_2O_{(l)}$

The cell display.

$Sn^{2+}_{(l)}\ \lvert\ Sn_{(n)}\ \Vert\ Cr_2O^{2-}_{(aq)}\ \lvert \ Cr^{3+}_{(aq)}\ where,$

$\lvert\ represents\ phase\ boundary\ and\newline \Vert\ represents\ salt\ bridge$