x/y = 3/4
x+10/y-10 = 1/1 => x+10 = y-10
=> x+20 = y
=>
x/(x+20) = 3/4
=> 4x = 3x + 60 <=> x = 60
=> y = x+20 = 80
=> X = Nd (neodim) , Y = Hg (mercur)
Hg, Z = 80
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10
grupa 12 (II-B) , perioada 6
Nd, Z = 60
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f4
seria Lantanide , perioada 6
