Week 3 - Powerpoint 1

• What is the shape of s-orbitals?


  Spherical
• How many orbitals make up the p subshell?


  3
• How many orbitals make up the d subshell?


  5
• In what order do electrons fill orbitals and subshells?


  Electrons fill from lower to higher energy levels
• How can you deduce the electron configuration of an atom given its atomic number?


  By filling the orbitals according to the number of electrons
• Who made the first convincing argument for the existence of atoms?

  John Dalton
• What did John Dalton's atomic theory state about atoms of a given element?


  They have the same mass and properties
• What are isotopes?


  Atoms with the same number of protons but different numbers of neutrons
• What is the atomic mass of an element based on?


  A weighted average of the masses of its isotopes
• How is atomic mass calculated?

  Using the formula: Atomic mass = (Fraction of isotope 1 × Mass of isotope 1) + ...
• What did Dimitri Mendeleev contribute to chemistry?


  He arranged the 60 known elements into the Periodic Table
• What are the vertical columns of the periodic table called?

  Groups
• What are the horizontal rows of the periodic table called?

  Periods
• What are the four blocks of the periodic table labeled as?


  s, p, d, and f
• What is the first sub-atomic particle discovered?


  The electron
• What determines the chemical properties and reactivity of elements?


  The number and arrangement of electrons
• What is the principal quantum number?


  It is the number assigned to each energy level or shell
• How many electrons can the third energy level hold?


  18
• What happens when filling electron shells?


  Electrons fill each shell fully before entering the next shell
• What are the maximum number of electrons for each energy level?


  • First (n=1): 2 electrons
  • Second (n=2): 8 electrons
  • Third (n=3): 18 electrons
  • Fourth (n=4): 32 electrons
• What are subshells?


  Subshells describe the specific orbit of an electron around the nucleus
• How can subshells be represented?


  They can be drawn as geometric shapes
• What is the octet rule?


  Atoms tend to have eight electrons in their outer shell
• What is the order in which levels and sublevels fill?


  1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f
• What is Hund's rule?


  When orbitals of identical energy are available, all are first occupied singly by electrons with parallel spins
• What are the two common representations of electron configuration?


  • Full electron configuration
  • Noble gas shorthand notation
• Why do noble gases have full energy levels?


  Because they have a complete set of electrons in their outer shell
• What is the electron configuration for sodium (Na) with atomic number 11?


  1s² 2s² 2p⁶ 3s¹
• What is the electron configuration for chromium (Cr)?


  [Ar] 3d⁵ 4s¹
• What is the electron configuration for molybdenum (Mo)?


  [Kr] 4d⁵ 5s¹
• What is the electron configuration for palladium (Pd)?


  [Kr] 4d¹⁰
• What is the electron configuration for silver (Ag)?


  [Kr] 4d¹⁰ 5s¹
• What is the electron configuration for gold (Au)?


  [Xe] 4f¹⁴ 5d¹⁰ 6s¹
• What are valence electrons?


  Electrons in the outermost energy level involved in chemical bonding
• What are core electrons?


  Electrons not in the outermost shell that are not involved in chemical bonding
• How can the periodic table be divided based on outermost electrons?


  • Into four blocks: s, p, d, and f
• Can you write the electron configuration for calcium (Ca)?


  1s² 2s² 2p⁶ 3s² 3p⁶ 4s²
• Can you write the electron configuration for arsenic (As)?


  [Ar] 4s² 3d¹⁰ 4p³
• Can you write the electron configuration for iron (Fe)?


  [Ar] 4s² 3d⁶
• Can you write the electron configuration for silver ion (Ag²⁺)?


  [Kr] 4d¹⁰