The standard reduction potentials at \( 298 \, \text{K} \) for the following half cells are given below:
\( \mathrm{NO_3^-} + 4\mathrm{H^+} + 3e^- \rightarrow \mathrm{NO(g)} + 2\mathrm{H_2O} \quad E^\ominus= 0.97 \, \text{V} \)
\( \mathrm{V^{2+}}(\mathrm{aq}) + 2e^- \rightarrow \mathrm{V} \quad E^\ominus = -1.19 \, \text{V} \)
\( \mathrm{Fe^{3+}}(\mathrm{aq}) + 3e^- \rightarrow \mathrm{Fe} \quad E^\ominus = -0.04 \, \text{V} \)
\( \mathrm{Ag^{+}}(\mathrm{aq}) + e^- \rightarrow \mathrm{Ag(s)} \quad E^\ominus = 0.80 \, \text{V} \)
\( \mathrm{Au^{3+}}(\mathrm{aq}) + 3e^- \rightarrow \mathrm{Au(s)} \quad E^\ominus = 1.40 \, \text{V} \)
The number of metal(s) which will be oxidized by \( \mathrm{NO_3^-} \) in aqueous solution is ________ .
