Recording-2025-02-25T16:00:03.386Z

Electron Configurations and Stability

• Valence Electrons in S and P Blocks

  • Elements in the s and p blocks aim for a total of eight or zero electrons in their valence orbitals.

  • Exception: Hydrogen and Helium (global gases) have only two valence electrons.

• Ion Predictions

  • To achieve stability, elements can:

    • Gain Electrons: For example, an element can gain five electrons to form a -5 charge.

    • Lose Electrons: Alternatively, an element can lose three electrons to achieve a stable state.

  • Elements like nitrogen and phosphorus typically form a -3 charge.

Octet Rule in D and F Blocks

• D and F Block Elements

  • Unlike s and p blocks, d and f block elements do not strictly adhere to the octet rule.

  • The d block elements consider both s and d orbitals when determining valence electrons.

  • D block elements tend to lose s electrons before d electrons during reactions.

• Example: Gold (Au) and its Ions

  • The gold ion can be represented as Au^{3+}.

  • To find the number of unpaired electrons in gold, it’s necessary to fill according to quantum orbitals.

  • Gold's electron configuration: Xenon (Xe) 4f^{14} 5d^{8}, losing both s and one d electron during ionization.

Understanding Electron Spins

• Characteristics of Unpaired Electrons:

  • Unpaired electron configurations must show the spins in half-filled orbitals.

  • For instance, dysprosium (Dy) electron configuration is discussed:

    • Dysprosium's Ionic Form: Dy^{3+} loses all its 6s electrons leading to an electron configuration of 4f^{9}.

Types of Chemical Bonding

• Covalent vs Ionic Bonding

  • Covalent Bonding: Involves nonmetals or semimetals, forms molecules without any overall charge.

    • Example: H2 (two hydrogen atoms create a shared electron bond).

  • Ionic Bonding: Occurs between a metal and a nonmetal, where atoms gain or lose electrons to achieve charge balance.

• Note: When no metals are involved, the assumption defaults to covalent bonding.

Molecule Formation and Charges

• Molecule appealing nature:

  • Atoms share electrons to achieve stability, resulting in a bond that allows for charge neutrality.

  • Each electron pair in the bond counts towards both atoms' stability. For instance, in H2, both atoms contribute to a shared pair of electrons to fulfill the octet rule, configured as an even bond.