What is the general outer configuration of the coinage metals?

\((n – 1) d^{10} ns^1\)

The answer is (3), \((n – 1) d^{10} ns^1\).

The coinage metals are copper (Cu), silver (Ag), and gold (Au). Their outermost electronic configurations are \((n – 1) d^{10} ns^1\). This means that they have a full d subshell and a single electron in the s subshell.

The other answer choices are incorrect. Option (1), \(ns^2np^6\), is the general outer configuration of the noble gases. Option (2), \((n – 1)d^9 ns^2\), is the general outer configuration of the transition metals that have one less electron in the d subshell than the coinage metals. Option (4), \((n – 1) d^{10} ns^2\), is the general outer configuration of the transition metals that have a full d subshell.