How much energy $\backslash ($ E $\backslash )$ in electronvolts $\backslash ((\backslash$mathrm$\{$eV$\})\backslash )$ is needed to ionize a hydrogen atom that starts in the Bohr orbit represented by $\backslash ($ n$=2\backslash )?$

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If an atom is ionized, its outer electron is no longer bound to the atom.