How many d electrons (n of dn) are in the central metal ion in the species below? (a) [ru(nh3)5cl]so4 6 d electrons (b) na2[os(cn)6] 6 d electrons?

(a) [Ru(NH₃)₅Cl]SO₄

The number of d electrons in the valence shell of Ru³⁺ is 5.

Also the total number of d electrons in Ru³⁺ is 15

(b) Na₂[Os(CN)₆]

The number of d electrons in the valence shell of Os⁴⁺ is 4.

Also the total number of d electrons in Os⁴⁺ is 24

Explanation:

In a coordination complex, a central metal is bonded to neutral or charged atoms or molecules, called ligands via coordinate covalent bonds.

(a) [Ru(NH₃)₅Cl]SO₄

The central metal atom is Ru

The electron configuration of Ru in ground state: 1s² 2s² 2p⁶ 3s² 3p⁶  3d¹⁰ 4s² 4p⁶ 4d⁷ 5s¹

Let the oxidation state of Ru in the given complex be x

∴ [x × 1] + [(0) × 5] + [(-1) × 1] + [(-2) × 1] = 0

⇒ x + 0 - 1 - 2 = 0

⇒ x = +3

Electron configuration of Ru³⁺: 1s² 2s² 2p⁶ 3s² 3p⁶  3d¹⁰ 4s² 4p⁶ 4d⁵

The number of d electrons in the valence shell of Ru³⁺ is 5

Also the total number of d electrons in Ru³⁺ is 15

(b) Na₂[Os(CN)₆]

The central metal atom is Os

The electron configuration of Os in ground state: 1s² 2s² 2p⁶ 3s² 3p⁶  3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d⁶ 6s²

Let the oxidation state of Os in the given complex be x

∴ [x × 1] + [(0) × 5] + [(-1) × 1] + [(-2) × 1] = 0

⇒ x + 0 - 1 - 2 = 0

⇒ x = +3

Electron configuration of Os⁴⁺: 1s² 2s² 2p⁶ 3s² 3p⁶  3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d⁴

The number of d electrons in the valence shell of Os⁴⁺ is 4

Also the total number of d electrons in Os⁴⁺ is 24