Which table row concerning silicon, Si, and magnesium, Mg, and their ions is correct?
- ASi has a greater atomic radius than Mg; Si has electrons in 3p orbitals, Mg has electrons in the 3s orbital only.
- BSi has a lower electrical conductivity than Mg; Si has 4 delocalised electrons per atom, Mg only has 2 delocalised electrons per atom.
- CSi has a lower melting point than Mg; Si has covalent bonding, Mg has metallic bonding.
- DThe radius of $\text{Si}^{4+}$ is smaller than the radius of $\text{Mg}^{2+}$; Si has a greater nuclear charge than Mg.