Chemistry of p-Block Elements - Key Concepts:

Group 13 Elements (Boron Family)

• Electronic Configuration:

  • General: ns2np1
  • Boron: 1s22s22p1

• Oxidation States:

  • +3 (most common)

• Boric Acid (H3BO3):

  • Weak acid
  • Forms esters

• Lewis Acidity of Boron Halides:

  • BF3 is the strongest Lewis acid among all BX3 halides
  • Lewis acidity: BF3 > BCl3 > BBr3 > BI3

Group 14 Elements (Carbon Family)

• Electronic Configuration:

  • General: ns2np2
  • Carbon: 1s22s22p2

• Oxidation States:

  • +4, +2 (for carbon, only -4 to +4)

• Catenation and Allotropy of Carbon:

  • Catenation: Ability to form long chains of C atoms
  • Allotropes: Diamond, graphite, fullerene, etc.

• Important Compounds of Carbon:

  • Saturated hydrocarbons (alkanes)
  • Unsaturated hydrocarbons (alkenes and alkynes)
  • Aromatic compounds

• Silicates and their properties:

  • Minerals containing SiO44- unit
  • Most abundant minerals on earth
  • Found in rocks, sand, clay

Group 15 Elements (Nitrogen Family)

• Electronic Configuration:

  • General: ns2np3
  • Nitrogen: 1s22s22p3

• Oxidation States:

  • +5, +3, -3 (for nitrogen, -3 to +5)

• Properties and uses of nitrogen compounds:

  • Ammonia (NH3): Fertilizer, refrigerant, precursor for nitric acid
  • Nitric Acid (HNO3): Strong acid, used in fertilizer and explosives
  • Nitrogen oxides: Air pollutants, play role in acid rain

• Phosphoric Acid (H3PO4):

  • Triprotic acid
  • Used in fertilizers, detergents

Group 16 Elements (Oxygen Family)

• Electronic Configuration:

  • General: ns2np4
  • Oxygen: 1s22s22p4

• Oxidation States:

  • -2, +2, +4, +6 (for oxygen, -2 to +6)

• Allotropic forms of Sulfur:

  • Rhombic sulfur
  • Monoclinic sulfur

• Sulphuric Acid (H2SO4):

  • Strong diprotic acid
  • Most industrially produced chemical
  • Used in fertilizers, batteries

Group 17 Elements (Halogens)

• Electronic Configuration:

  • General: ns2np5
  • Fluorine: 1s22s22p5

• Oxidation States:

  • -1

• Properties and uses of halogens:

  • Highly reactive
  • Form salts with metals
  • Used as disinfectants, bleaches

• Hydrohalic Acids and their properties:

  • Strong acids
  • Corrosive
  • React with metals to form salts

Group 18 Elements (Noble Gases)

• Electronic Configuration:

  • General: ns2np6
  • Helium: 1s2

• Noble Gas Character:

  • Chemically unreactive
  • Complete octet configuration
  • Low boiling points

Coordination Complexes:

• Nomenclature and Classification:

  • Ligands: Molecules or ions that bind to metal ions
  • Coordination number: # of ligands bonded to metal ion
  • Oxidation state of metal

• Bonding and Stability:

  • Metal-ligand bonds: coordinate covalent bonds
  • Stability of complexes: influenced by ligand properties, metal ion charge, and geometry

• Isomerism in Coordination Compounds:

  • Structural isomerism
  • Stereoisomerism: enantiomers and diastereomers

• Applications of coordination compounds:

  • Catalysts: facilitate chemical reactions
  • Pharmaceuticals: drugs and medicines
  • Pigments: provide color
  • Magnetic materials