Which of the following statements is correct for the cell $Zn|Zn^{2+} \parallel Cu^{2+}|Cu$?

What is electrochemistry? Give the uses of electrochemistry.

Which relation is correct for $\Lambda^0_{m(H_2O)}$?

Fill in the blanks :
$(1)$ In a galvanic cell,the anode and cathode possess $\dots$ and $\dots$ charge respectively.
$(2)$ According to convention,the anode and cathode in a galvanic cell are present on the $\dots$ and $\dots$ side respectively.

Which substance is reduced in a dry cell?

The standard reduction potentials at $298 \ K$ for the following half-cells are given below:
$Cr_2O_7^{2-} + 14H^+ + 6e^- \rightarrow 2Cr^{3+} + 7H_2O$,$E^{\circ} = 1.33 \ V$
$Fe^{3+} + 3e^- \rightarrow Fe$,$E^{\circ} = -0.04 \ V$
$Ni^{2+} + 2e^- \rightarrow Ni$,$E^{\circ} = -0.25 \ V$
$Ag^+ + e^- \rightarrow Ag$,$E^{\circ} = 0.80 \ V$
$Au^{3+} + 3e^- \rightarrow Au$,$E^{\circ} = 1.40 \ V$
Consider the given electrochemical reactions. The number of metal$(s)$ which will be oxidized by $Cr_2O_7^{2-}$ in aqueous solution is $.....$