Nickel ground state electronic configuration

Write out the ground state electronic configurations for (a) magnesium, (b) silicon, and (c) nickel. 

Because the 4s-electrons are lost first when transition metals form ions, you may prefer to write the ground state electronic configuration of a transition metal with the 4s-subshell coming after the 3d-subshell, as shown below for vanadium, iron, and nickel. This is acceptable, but remember, the 4s-subshell fills before the 3d-subshell in the building-up process. 

The ground-state electronic configuration of iron in the solid-state metal lattice is [Ar] 4s 3d . The magnetic moment per iron atom in a cm solid is 2.2 X 10 emu, or approximately 2 Bohr magnetons = 1 x 10 emu). Therefore, there are two unpaired electrons in each iron atom throughout the lattice. By comparison, the fx-B values for cobalt ([Ar] 4s 3d ) and nickel ([Ar] 4s 3d ) arc 1.72 and 0.61, respectively. Since there are five d orbitals and six d-electrons for iron, two separate... 

Most of the nickel compounds in the solid state and almost all in aqueous solution contain the metal in the oxidation state +2, which, by consequence, can be considered the ordinary oxidation state for nickel in its compounds. The electronic structure and stereochemistry of nickel(II) were reviewed in 1968.6 The most stable electronic configuration of the free Ni ion is [Ar]3d8 which is also the ground state configuration in its complexes. The overwhelming majority of nickel(II) complexes have coordination numbers of four, five and six. Complexes with coordination numbers of three, seven and eight are still quite rare. 

The starting point for most of the redox chemistry considered in this review is the nickel(II) ion. The nickel(II) ion has a d8 electronic configuration and, with weak-field ligands such as H20, it forms a six-coordinate ion with approximately octahedral symmetry and a paramagnetic (two unpaired electrons) 3A2 ground state. The characteristic solution chemistry of six-coordinate nickel(II) is well documented and, in particular, the substitution behavior has been extensively studied and is the subject of recent reviews (11, 12). It is a labile ion with solvent exchange rates around 104 sec-1 at 25°C and activation parameters are consistent with dissociatively activated interchange behavior (13). 

As vanadium(m) has a d2 electron configuration with a triply degenerate ground state in octahedral symmetry, pseudooctahedral vanadium(III), in analogy to pseudotetrahedral nickel(II), is expected to display short electronic relaxation times. 

Describe the electrons in an atom of nickel in the ground state using the electron configuration notation and the noble-gas notation. 

Give the electron configuration of the ground state of nickel, using the building-up principle. 

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