In . cadmium Cd . silver Ag . palladium Pd .
rhodium Rh . ruthenium Ru . technetium Tc [ ] molybdenum Mo . niobium Nb .
zirconium Zr . yttrium Y . strontium Sr . rubidium Rb .
radon Rn [ ] astatine At [ ] polonium Po [ ] bismuth Bi . lead Pb . dysprosium Dy . terbium Tb .
gadolinium Gd . europium Eu . samarium Sm . promethium Pm [ ] neodymium Nd .
praseodymium Pr . cerium Ce . lanthanum La . barium Ba .
caesium Cs . roentgenium Rg [ ] Copernicium Cn [ ] Nahonium Nh [ ] Flerovium Fl [ ] Mascovium Mc [ ] Livermorium Lv [ ] Tennessine Ts [ ] Oganessom Og [ ] darmstadtium Ds [ ] meitnerium Mt [ ] hassium Hs [ ] bohrium Bh [ ] seaborgium Sg [ ] dubnium Db [ ] rutherfordium Rf [ ] radium Ra [ ] francium Fr [ ] lutetium Lu . ytterbium Yb . thulium Tm .
erbium Er . holmium Ho . thallium Tl . mercury Hg .
gold Au . platinum Pt . iridium Ir . osmium Os .
rhenium Re . tungsten W . tantalum Ta . hafnium Hf .
berkelium Bk [ ] lawrencium Lr [ ] nobelium No [ ] mendelevium Md [ ] fermium Fm [ ] einsteinium Es [ ] californium Cf [ ] curium Cm [ ] americium Am [ ] plutonium Pu [ ] neptunium Np [ ] uranium U . protactinium Pa . thorium T . actinium Ac [ ] s-Block d-Block p-Block f-Block Electronic configuration of Lanthanoids: We know that the electrons are filled in different orbitals in the order of their increasing energy in accordance with Aufbau principle.
As per this rule after filling 5s,5p and 6s and 4f level begin