Unit 1: Alchemy Scientific Method Quiz

Unit 1: Alchemy

• Scientific Method: A systematic approach to observation, measurement, experimentation, and hypothesis refinement.
• Steps of the Scientific Method: Observation → Hypothesis → Experiment → Theory/Law
• Theory: An explanation of natural behavior.
• Law: A description of measurable, observed behavior.
• Experiment: A scientific procedure performed to discover, test a hypothesis, or demonstrate facts.
• Hypothesis: A proposed explanation, based on limited evidence, for further testing.
• Observation: A remark based on something seen, heard, or noticed.
• Theory Model: A representation to help understand a process.
• Significant Figures: All known digits plus one estimated digit in a measurement.
• Significant Figures Rules:
  • Nonzero digits are significant.
  • Leading zeros are not significant.
  • Captive zeros are significant.
  • Trailing zeros are significant only if the number contains a decimal point.
• Measurement and Scientific Notation: Expressing numbers as a coefficient multiplied by a power of 10.
  • Exponents are positive if the number is greater than 10, negative if less than 1.
• Significant Figures Operations: In addition/subtraction, the answer has the same number of decimal places as the measurement with the fewest decimal places. In multiplication/division, the answer has the fewest significant figures as the measurement with the fewest significant figures.
• Dimensional Analysis: A problem-solving method using unit conversions.
  • Start with the desired result, then list givens.
  • Determine conversion factors from SI units.
• SI Units: Standard units of measure for a given quantity.

Unit 2: Basic Building Blocks

• Matter: Anything with mass and volume.
• Substance: Matter with a uniform and definite composition (e.g., sugar, water).
• Element: A substance containing atoms of only one type.
• Atom: Basic unit of an element.
• Compound: Substance formed by two or more elements chemically combined.
• Chemical Formula: Symbols representing a compound's composition.
• Subscripts: Numbers in a chemical formula indicating atom ratios.
• Physical Properties: Characteristics that can change without changing the substance’s composition (e.g., color, melting point, density).
• Physical Change: Change in appearance without changing composition.
• Chemical Properties: Characteristics describing a substance's ability to change to a different substance (e.g., flammability).
• Chemical Change: Results in a new substance with a different chemical formula.
• Indicators of a Chemical Change: Gas production, precipitate formation, color change, temperature/energy change.
• Mixture: A physical blend of two or more substances.
• Homogenous Mixture: Uniform throughout (e.g., sugar water).
• Heterogenous Mixture: Not uniform throughout (e.g., blood, concrete).
• Law of Conservation of Mass: Mass is neither created nor destroyed in a chemical reaction.
• Subatomic Particles:
  • Neutron: Neutral, in the nucleus, 1 amu.
  • Proton: Positive, in the nucleus, 1 amu.
  • Electron: Negative, electron cloud region, very small mass.
• Atomic Number: Number of protons in an atom.
• Mass Number: Number of protons plus neutrons in an atom.
• Isotope: Atoms of the same element with different numbers of neutrons.
• Atomic Mass (Weight): Weighted average mass of an element's isotopes.
• Ion: Atom that has gained or lost electrons.
  • Cation: Positive ion.
  • Anion: Negative ion.
• Dead Chemists (and their contributions): (List from summary, omit names.)

Unit 3: Subatomic Particles (Nuclear)

• Sun Formation: Formation of the Sun from a spinning cloud of gas and dust.
• Sun Composition: Primarily hydrogen and helium.
• Nuclear Fusion: Hydrogen nuclei combine to form helium.
• Chemical Reaction vs. Nuclear Reaction:
  • Chemical: Electrons involved, small energy release.
  • Nuclear: Nuclei involved, huge energy release.
• Gravitational Equilibrium: Balance between outward pressure and inward gravity in a star.
• Energy Reaches Earth: Photons carry energy from the sun to Earth (taking a long time).
• Radiation: Penetrating rays and particles from a radioactive source.
• Nuclear Forces: Strong attractive forces holding nuclear particles together.
• Nuclear Binding Energy: Energy released when forming a nucleus.
• Band of Stability: Range of stable isotopes (protons/neutrons).
• Half-Life: Time for half of a radioactive sample to decay.
• Fission: Splitting of a heavy nucleus.
• Fusion: Combining of light nuclei.
• Uses of Radioactive Materials: Medical diagnosis, carbon dating, etc.

Unit 4: A Particulate World - Electron Configuration

• Bohr Model: Electrons orbit the nucleus in discrete energy levels.
• Quantum of Energy: Energy needed for an electron to jump between energy levels.
• Electron Shells (Energy Levels): Discrete regions electrons occupy.
• Electron Shells Capacity: Maximum number of electrons in a shell (2n^2).
• Quantum Mechanical Model: Probability of finding an electron around the nucleus, not discrete orbits.
• Quantum Numbers: Describe the location of an electron around the nucleus.
• Sublevels (Orbitals): s, p, d, f (Different shapes and energy requirements.)
• Electron Configurations: Arrangement of electrons in atomic orbitals.
• Principal Quantum Number(n): Energy level
• Energy Sublevel (s, p, d, f): orbital type
• Electron Cloud Shape: Each shape corresponds to a sublevel or orbital
• Electron Configuration Rules
  • Aufbau: Fill the lowest energy orbitals first
  • Pauli Exclusion: A maximum of 2 electrons per orbital, opposite spins
  • Hund: Fill orbitals singly before pairing electrons.
• Atomic Spectra: Light emitted when electrons return to ground state.
• Ground State: Lowest energy electron configuration
• Excited State: Higher energy electron configuration
• Properties of Light Relationship Use equations to calculate light properties

Unit 5: Building with Matter

• Ions: Atoms that have gained or lost electrons
• Ionic Bonds: Attraction between (+)/(−) ions
• Covalent Bonds: Sharing of electrons between atoms
• Bond Energy: Energy needed to break or form a bond.
• Bond Length: Distance between bonded atoms.
• Polyatomic Ions: Ions composed of more than one atom.

Unit 6: Smells (Covalent Bonding)

• Empirical Formula: Simplest whole number ratio of atoms in a compound.
• Molecular Formula: Exact number and types of atoms in a molecule.
• Naming Covalent Compounds: Use prefixes to indicate the number of each element.
• Hydrocarbons: Compounds containing only carbon and hydrogen.
• Hydrocarbon Functional Groups:
  • Alkanes: Single bonds
  • Alkenes: Double bonds
  • Alkynes: Triple bonds
  • Aromatics: Benzene ring structures
• Functional Groups: Sets of atoms giving specific chemical/physical properties to organic molecules.
• Hybridization: Mixing atomic orbitals to create new hybrid orbitals.
• Intermolecular Forces (IMF's): Attractions between molecules (weaker than bonds).
• Dipole-dipole Forces: Attractions between polarized molecules.
• Hydrogen Bonds: Particularly strong type of dipole-dipole force.
• London Dispersion Forces: Weakest intermolecular force caused by temporary electron shifts.

Unit 7: Tracking Toxins

• Balancing Chemical Equations: Ensuring equal numbers of atoms on both sides of the reaction arrow.
• Reactants: Starting substances in a reaction.
• Products: Substances formed in a reaction.
• Coefficients: Numbers in front of formulas indicating the number of molecules.
• Subscripts: Numbers below elements indicating number of atoms in a molecule.