CHMA10H3 Chapter : ch8. Periodic Properties of the Elements.doc

• School: UTSC
• Department: Chemistry
• Course: CHMA10H3
• Professor: Shadi Dalili

Document Summary

Periodic properties of the elements: concepts of quantum mechanics explain the arrangement of elements in the periodic table by reference to the electrons within the atoms that compose the electrons. Electron configurations: how electrons occupy orbitals: electron configuration for an atom shows the particular orbitals that are occupied for that atom, ground state lowest energy state (ex: h. +1/2) or spin down (ms = -1/2: pauli exclusion principle no two electrons in an atom can. 1s22s22p63s23p2 in an atom (core electrons in complete principal energy levels and in complete d and f sublevels) ex: silicon has 4 valence electrons (in the n=3 principal level) and 10 core electrons. Orbital blocks in the periodic table: except for helium, the number of valence electrons for any main, highest principal level (n value) is given by the row number group element is equal to its lettered group number.