Chemistry deals with the composition, properties, and reactions of substances. For WBCS Prelims, the focus is on applied chemistry and common phenomena.

Important Topics:

• Matter & Its States:

  • Solid, Liquid, Gas

  • Changes in State (Melting, Boiling, Evaporation)

• Atoms & Molecules:

  • Atomic Number, Mass Number

  • Elements, Compounds, Mixtures

  • Chemical Symbols & Formulas

• Acids, Bases & Salts:

  • Properties and Uses

  • pH Value (Importance in Soil, Body, Industry)

  • Common Acids (HCl, H2SO4), Bases (NaOH), Salts (NaCl)

• Metals & Non-Metals:

  • Physical & Chemical Properties

  • Corrosion & Rusting

  • Alloys: Brass, Bronze, Steel

• Carbon & Its Compounds:

  • Organic Chemistry Basics

  • Fuels: Coal, Petrol, LPG

  • Plastics & Polymers

  • Environmental Impact of Plastics

• Chemical Reactions:

  • Combustion

  • Oxidation & Reduction

  • Photosynthesis (in Biology too)

• Water Chemistry:

  • Properties of Water

  • Hard & Soft Water

  • Purification Methods (Filtration, Distillation, Reverse Osmosis)