Chemistry and Optics Unit 1 & 2

Chemistry - U1

• Diatomic Elements: HOFBrINCl
• Naming Ionic Compounds: Metal name + non-metal name ending in "ide" (e.g., ZnCl₂ = Zinc Chloride)
• Naming Molecular Compounds: Use prefixes (mono-, di-, tri-, tetra-, penta-, hexa-) based on subscripts for both elements (e.g., N₂O = Dinitrogen Monoxide)
• Chemical Formulas: Use criss-cross method, considering periodic table patterns (1, 2, 3, 4, 3, 2, 1, 0)
• Example: Lithium Oxide (Li₂O)

Optics - U2

• Cations and Anions: Cations are positively charged ions (lose electrons), Anions are negatively charged ions (gain electrons)
• Angle of Incidence: Angle between incident ray and normal line.
• Angle of Reflection: Angle between reflected ray and normal line (equal to angle of incidence)
• Normal Line: Line perpendicular to the surface at the point of incidence.
• Incident Ray: Incoming light ray.
• Reflected Ray: Reflected light ray.
• Focus: Point where light rays converge or diverge.
• Principle Axis: Horizontal line through centre of mirror/lens, used for calculations.

Types of Mirrors and Lenses

• Concave Mirror: Image is always REAL, unless reflected outwards, where it is VIRTUAL
  • Ray parallel to PA is reflected through F
  • Ray through C reflects back on itself
  • Ray through F reflects parallel to PA
  • Ray aimed at V follows law of reflection
• Convex Mirror: Image is always VIRTUAL
  • Ray parallel to PA reflects as if through F
  • Ray aimed at C reflects back on itself
  • Ray aimed at F reflects parallel to PA
• Converging Lenses: Images are typically VIRTUAL.
  • Ray parallel to PA refracts through F
  • Ray through F' refracts parallel to PA
  • Ray through O continues straight

Optics - U2 (continued)

• Convex Lenses: Image is always VIRTUAL
  • Ray parallel to PA refracts through F
  • Ray through F' refracts parallel to PA
  • Ray through O continues straight

Biology - U3

• Cell Division: Essential for repair, reproduction, growth.
• Major Cell Organelles: Mitochondria (energy), Nucleus (control), Cell Wall (plant cells), Cell Membrane, Cytoplasm, Vacuole, Chloroplast.
• Functions of Systems: Digestive (breaks down food), Circulatory (moves nutrients/oxygen/waste), Respiratory (gas exchange).
• Connection of Systems: Nutrients absorbed in digestive system enter bloodstream; oxygen from lungs enters circulatory system to deliver to body.

Chemistry - U1 (continued)

• Law of Conservation of Mass: Mass of reactants equals mass of products.
• Polyatomic Ions: Ions containing multiple elements (e.g., nitrate, sulfate, phosphate)
• pH Scale: Measure of acidity/basicity. 0-6 acidic; 7 neutral; 8-14 basic.

Other

• Plant vs. Animal Cells (identification): Plant cells have chloroplasts and cell walls, animal cells have centrioles and lysosomes.
• Gas Exchange: Oxygen diffused into blood, CO₂ diffused out via capillaries in alveoli for removal.
• Refraction: Bending of light as it passes through different mediums
• Hyperopia: Farsightedness (image focused behind retina)
• Myopia: Nearsightedness (image focused in front of retina)
• Presbyopia: Age-related farsightedness due to decreased elasticity of the eye lens.