Key Concepts
- Matter exists as solid, liquid, gas.
- Properties depend on interparticle space and intermolecular force.
- Diffusion: mixing of particles on their own.
- Latent heat: heat required for change of state.
- Sublimation: solid → gas directly.
- Evaporation depends on:
- Temperature ↑
- Surface area ↑
- Wind speed ↑
- Humidity ↓
CHAPTER 2: Is Matter Around Us Pure?
Key Concepts
- Pure substance = elements + compounds.
- Mixture = homogeneous or heterogeneous.
- Separation methods:
- Filtration
- Evaporation
- Distillation
- Chromatography
- Centrifugation
- Sublimation
- Solution:
- Solute + solvent
- Concentration formula:
\text{Mass %} = \frac{\text{solute}}{\text{solution}} \times 100
CHAPTER 3: Atoms and Molecules
Key Concepts
- Law of Conservation of Mass (Lavoisier)
- Law of Constant Proportion (Proust)
- Atomic mass unit (amu)
- Mole concept:
1 mole=6.022×10231\ \text{mole} = 6.022 \times 10^{23}1 mole=6.022×1023 particles - Molecular mass = sum of atomic masses.
CHAPTER 4: Structure of the Atom
Key Concepts
- Thomson model: plum pudding.
- Rutherford model: nucleus + empty space.
- Bohr model: electrons in shells.
- Subatomic particles:
- Proton: +1
- Electron: –1
- Neutron: 0
- Isotopes: same atomic number, different mass number.
- Isobars: same mass number, different atomic number.
CHAPTER 5: The Fundamental Unit of Life
Key Concepts
- Cell is the basic unit of life.
- Prokaryotic vs Eukaryotic cells.
- Cell organelles:
- Nucleus
- Mitochondria (ATP)
- Golgi body
- ER (rough & smooth)
- Ribosomes
- Lysosomes
- Plastids
- Vacuole
- Plasma membrane = selectively permeable.
CHAPTER 6: Tissues
Plant Tissues
- Meristematic: apical, intercalary, lateral
- Permanent tissues:
- Simple: parenchyma, collenchyma, sclerenchyma
- Complex: xylem, phloem
Animal Tissues
- Epithelial
- Connective (blood, bone, cartilage, areolar)
- Muscular
- Nervous
CHAPTER 7: Diversity in Living Organisms
Hierarchy
Kingdom → Phylum → Class → Order → Family → Genus → Species
Five Kingdoms (Whittaker)
- Monera
- Protista
- Fungi
- Plantae
- Animalia
Plant groups
- Thallophyta
- Bryophyta
- Pteridophyta
- Gymnosperms
- Angiosperms
CHAPTER 8: Motion
Key Formulas
- Speed = distance/time
- Velocity = displacement/time
- Acceleration = change in velocity/time
- Uniform motion vs Non-uniform motion
- Graph: slope of velocity-time graph = acceleration
- Equations of motion:
- v=u+atv = u + atv=u+at
- s=ut+12at2s = ut + \frac{1}{2}at^2s=ut+21at2
- v2−u2=2asv^2 – u^2 = 2asv2−u2=2as
CHAPTER 9: Force and Laws of Motion
Newton’s Laws
- 1st Law: inertia
- 2nd Law: F=maF = maF=ma
- 3rd Law: action = reaction
Inertia Types
- Inertia of rest
- Inertia of motion
- Inertia of direction
Momentum
p=mvp = mvp=mv
CHAPTER 10: Gravitation
Universal Law
F=Gm1m2r2F = G \frac{m_1 m_2}{r^2}F=Gr2m1m2
Free fall
g=9.8 m/s2g = 9.8\ m/s^2g=9.8 m/s2
Mass vs Weight
- Mass = constant
- Weight = mgmgmg
Buoyancy
- Upthrust in fluids
- Archimedes’ principle
CHAPTER 11: Work and Energy
Work
W=F⋅sW = F \cdot sW=F⋅s
Energy
- Kinetic energy:
KE=12mv2KE = \frac{1}{2} mv^2KE=21mv2 - Potential energy:
PE=mghPE = mghPE=mgh
Power
P=W/tP = W/tP=W/t
CHAPTER 12: Sound
- Sound → longitudinal waves
- Speed of sound: solids > liquids > gases
- Frequency defines pitch
- Amplitude defines loudness
- Human hearing range: 20 Hz – 20,000 Hz
CHAPTER 13: Why Do We Fall Ill?
Health depends on:
- Good diet
- Clean environment
- Mental well-being
- Social stability
Types of diseases
- Acute
- Chronic
- Infectious
- Non-infectious
Infectious agents
Virus, bacteria, fungi, protozoa, worms.
CHAPTER 14: Natural Resources
- Air, water, soil
- Biogeochemical cycles → water cycle, nitrogen cycle, carbon cycle
- Greenhouse effect
- Ozone depletion
CHAPTER 15: Improvement in Food Resources
Crop improvement
- High-yielding varieties
- Fertilisers & manure
- Irrigation methods
- Crop rotation
Animal husbandry
- Poultry
- Fish farming
- Cattle management