There is no strictly relationship, but for NON-transition metals (i.e. Non-d-block, non-f-block), over there is one.
Valence electrons are then USUALLY detailed after the noble gas core, within factor (e.g. Tungsten, #"W"#, probably doesn"t have #20# valence electrons, but up come #6# instead).
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For NON-transition metals, the energy level #n# is offered by its duration number, i.e. That row number. Gift on the fourth row the the periodic table way your valence electrons would be the #4s# and #4p# electrons, #n = 4#.
Two examples:
#"Ca"#, with configuration #
#"P"#, through configuration #
EXCEPTIONS BELOW!
Transition metals on the various other hand have actually easy access to occupied #(n-1)d# orbitals, and also thus have actually the electrons in those orbitals included in their set of valence electrons.
Three examples:
#"Sc"# (scandium), with configuration #
#"W"# (tungsten), v configuration #
#"Os"# (osmium), v configuration #
Some heavy #bb(f)#-block metals (mainly lanthanides and actinides) likewise have access to occupied #(n-2)f# orbitals too, and those electron might likewise be had in their collection of valence electrons... They might even not have actually #(n-1)d# valence electron sometimes.
Three examples:
#"Pa"# (protactinium), through configuration #
#"Bk"# (berkelium), through configuration #
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#"Gd"# (gadolinium), with configuration #