علم الكيمياء: الذرات والخصائص

Science

• Atom: Smallest unit of an element
• Heterogeneous mixture: Mixture whose components can be separated
• Homogeneous mixture: Mixture whose components cannot be separated
• Physical property: Changes that can be observed without changing the substance (color, melting/boiling point)
• Chemical property: Changes observed after a chemical reaction (flammability)
• Intensive property: Doesn't depend on the amount of matter (density, temperature, color)
• Extensive property: Depends on the amount of matter (mass, volume, moles)
• Viscosity: Resistance of a liquid to flow (e.g., honey)
• Isotopes: Elements with the same number of protons but different mass numbers

Atomic Theories

• Democritus (500 BC): Proposed that all matter is composed of indivisible particles
• John Dalton (1803): Introduced the concept of the atom, visualized as a solid sphere.
• J.J. Thompson (1904): Developed the Plum Pudding model, where negatively charged particles are embedded in a positively charged sphere.
• Ernest Rutherford (1911): Proposed the Nuclear model, with a small, dense, positively charged nucleus containing most of the mass.
• Niels Bohr (1913): Proposed the Planetary model, where electrons orbit the nucleus in specific energy levels
• Erwin Schrödinger (1926): Developed the Quantum model, describing electrons as existing in probability clouds (orbitals) rather than fixed paths.

Mixtures

• Mixture: A combination of two or more substances that retain their individual properties.
• Covalent compounds: Naming convention for covalent compounds: "Add ide to the end of the second element, use mono-, di-, tri-, etc. to indicate the number of each element."
  • Examples: (e.g. mono-di-, tri-, tetra-, penta-)

Moles and Molar Mass

• Mole: A unit representing 6.022 x 10²³ elementary units of a substance.
• Molar mass: The mass of one mole of a substance (in grams)
  • For atoms, the molar mass is numerically equal to its atomic mass.
  • For molecules, it is the sum of the atomic masses of all atoms in the molecule.
  • Example: Water (H₂O): 18.015 grams per mole

Biomolecules

• Biomolecules: Essential for life, combinations of Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, Sulfur ("CHONPS").

Cellular Respiration, Cell Division, and Flowers

• Cellular Respiration: Process where cells convert glucose into ATP
• Protein Synthesis: Ribosome function in cells.
• Cell Membrane: Regulates the movement of substances into and out of the cell.
• Mitochondria: Site of the Krebs cycle; known as the powerhouse of the cell.
• Mitosis: Cell division in non-reproductive cells, producing two identical daughter cells.
• Meiosis: Cell division in reproductive cells (sperm/egg), producing four daughter cells (haploid).
• Flowers: Categories of flowers include perfect (having male and female parts), imperfect (having one type of reproductive part), complete (having all flower parts), and incomplete (lacking some flower parts).

Mendelian Genetics

• Allele: Different versions of a DNA sequence.
• Dominant Allele: Determines the organism's characteristics.
• Recessive Allele: Characteristic is masked when a dominant allele is present.
• Law of Segregation: Each organism has two alleles for each gene, which separate during meiosis.
• Steps of Mitosis Detailed stages of Mitosis (PPMAT: Prophase, Prometaphase, Metaphase, Anaphase, Telophase, Cytokinesis).

Animal Relationships; Transpiration

• Animal Relationships: Predation (one organism eats another), parasitism (one benefits at the expense of the other), mutualism (both benefit), and commensalism (one benefits, the other is unaffected)
• Transpiration: Plants move water from roots to leaves

Other Topics (Pages 3, 4)

• DNA: Genetic material
• Insulin: Hormone that regulates blood glucose
• Scalar Quantities: Described by magnitude only
• Vector Quantities: Described by magnitude and direction.
• Thermodynamics: Zeroth, First, Second, and Third Laws (explaining thermal equilibrium, energy transformation, entropy, and the relationship to absolute zero)
• Archimedes' Principle: Describes the buoyant force on a submerged object.
• Waves: Disturbances that travel and carry energy. (Mechanical and Electromagnetic waves, wave properties).

Other Topics (Pages 5-9)

• Geological Time Scale: Overview of Earth's history, periods, and eras.
• Discourse: A form of communication like writing or speaking used for analysis or discussion. Types included: persuasion (to convince), description, exposition, narration, etc. Discourse types are found in academic, business, and artistic contexts
• Kinds of Nonverbal Communication: Examples such as paralanguage, gestures, facial expressions, etc.
• Elements of Communication: Including the sender, message, encoding, channel, decoding and receiver, and feedback
• Fallacies: Logical errors in arguments (Ad Hominem, Ad Verecundiam, Bandwagon, etc).
• Wave Phenomena: Reflection, refraction, diffraction, and interference.
• Types of Rocks: Igneous (intrusive/extrusive), Metamorphic (foliated/non-foliated), Sedimentary (classic/chemical/organic)
• Literary Discourse: Types of discourse in literature or essays (primarily transactional, poetic, and expressive).
• Specific Fallacies: (e.g., Accent, Amphiboly, Complex Question, Equivocation, etc.)

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