Silicon atoms have 14 electrons. The ground state electron configuration of ground state gaseous neutral silicon is 1s²2s²2p⁶3s²3p².
Using noble gas shorthand, the electronic configuration is reduced to;
[Ne] 3s² 3p². Ne s the nearest noble gas to silicon, Ne contains 8 electrons, this means there's still 4 more electrons to fill. The s orrbital can only hold 2, hence the reaing two is transferred to the p orbital.
If you are given the
standard potential for the reduction of X^2+ is +0.51 V, and the standard
potential for the reduction of A^2+ is -0.33, just add the two. The standard
potential for an electrochemical cell with the cell is 0.18V