Which one of the following pairs are isoelectronic? a. Mn2+ and Ar b. zn 2+ and Cu2+ c. Na+ and K+ d. Cl- and S e. K+ and Cl?
- ArgentLv 71 month ago
a. Mn²⁺ is the same as [Ar] 3d⁵, which is definitely not isoelectronic with argon.
b. Zn²⁺ is the same as Cu⁺, not Cu²⁺, so no match here.
c. Na⁺ has lost its one valence electron, so is isoelectronic with a noble gas (neon).
K⁺ has also lost its one valence electron, so is isoelectronic with a noble gas (argon).
d. Cl⁻ has the electron configuration of argon, which is not the configuration of neutral sulfur.
e. K⁺ is isoelectronic with neutral argon, not neutral chlorine.