Explain the construction of a galvanic cell based on the Daniell cell. In a galvanic cell,explain the positive and negative electrodes with suitable chemical reactions.

(N/A) Construction of a galvanic cell based on the Daniell cell: We can construct various galvanic cells following the pattern of the Daniell cell by using different combinations of half-cells.
$(i)$ Each half-cell consists of a metallic electrode dipped into an electrolyte solution.
$(ii)$ The two half-cells are connected externally by a metallic wire through a voltmeter and a switch.
$(iii)$ The electrolytes of the two half-cells are connected internally through a salt bridge. In some cases,both electrodes may dip into the same electrolyte solution,in which case a salt bridge is not required.
$(b)$ Positive and negative electrodes and reactions in the Daniell cell:
Positive electrode (Cathode): At the electrode-electrolyte interface,metal ions from the solution tend to deposit on the metal electrode,making it positively charged.
$M^{n+}_{(aq)} + ne^{-} \longrightarrow M_{(s)}$ (Reduction)
In the Daniell cell,the $Cu$ electrode acts as the cathode (positive electrode),where the reduction reaction occurs.
Negative electrode (Anode): Metal atoms of the electrode tend to enter the solution as ions,leaving behind electrons on the electrode,making it negatively charged.
$M_{(s)} \longrightarrow M^{n+}_{(aq)} + ne^{-}$ (Oxidation)
In the Daniell cell,the $Zn$ electrode acts as the anode (negative electrode),where the oxidation reaction occurs.