Nature of Matter
Everything around us—books, water, air, living beings—is matter! 💫 Matter has mass and occupies space.
🧊 States of Matter
Matter exists in 3 states:
- Solids: Definite shape + volume. Particles packed tightly in order. 🔒
- Liquids: Definite volume, no definite shape (takes container shape). Particles move around. 💧
- Gases: No definite shape or volume (fills container). Particles far apart, move fast. 💨
States change with temperature/pressure:
Solid \(\xrightarrow{\text{heat}}\) Liquid \(\xrightarrow{\text{heat}}\) Gas
Gas \(\xrightarrow{\text{cool}}\) Liquid \(\xrightarrow{\text{cool}}\) Solid
🔬 Classification of Matter
Pure substances have identical particles. Mixtures contain multiple substances mixed together.
➡️ Pure substances:
- Elements: Made of one atom type (e.g., sodium, oxygen).
Atoms may exist alone (e.g., copper) or as molecules (e.g., O₂ = two oxygen atoms). - Compounds: Atoms of different elements in fixed ratios (e.g., H₂O, CO₂).
Properties differ from their elements (e.g., H₂ + O₂ = water 💦, which extinguishes fire!).
➡️ Mixtures:
- Homogeneous: Uniform composition (e.g., sugar water, air).
- Heterogeneous: Non-uniform composition (e.g., salt + sugar mix).
Mixtures can be separated by physical methods (filtration, distillation). Compounds need chemical methods! ⚗️
📏 Properties of Matter
- Physical properties: Observed without changing the substance (color, density, melting point).
- Chemical properties: Observed during chemical changes (combustibility, acidity, reaction with acids).
🚨 NEET High-Yield Concepts
- States of matter: Characteristics of solids, liquids, gases (definite shape/volume?).
- Pure vs. mixtures: Separation methods, homogeneous/heterogeneous examples.
- Elements & compounds: Differences, fixed composition in compounds (e.g., H₂O ratio).
- Physical vs. chemical properties: Measurement criteria (change in identity?).
- State interconversion: Role of temperature/pressure in phase changes.
Keep practicing—you’re getting closer to acing chemistry! 🔥
