Which ions have the electron configuration

CHEMISTRY · Single correct · AP · Chemistry · Atomic Structure and Properties · Atomic Structure and Properties

Problem

1\text{s}^2 2\text{s}^2 2\text{p}^6 3\text{s}^2 3\text{p}^6

? - I.

\text{Ca}^{2+}

II.

\text{Ti}^{4+}

III.

\text{Cu}^{2+}

(1) I and II (2) I and III (3) II and III (4) I, II and III