Respuesta :
Answer is: [Xe] 6s².
Barium is metal from second group of periodic table of elements.
Barium has atomic number 56, it has 56 protons and 56 electrons.
Electron configuration of barium atom:
₅₆Ba 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 6s².
Xenon (symbol: Xe) is an element (noble gas) with atomic number 54, which means it has 54 protons and 54 electrons.
Electron configuration of xenon atom:
₅₄Xe 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶.