Chemistry Review Notes Units 1-7: Regents Review

Unit 1 & 2: Math, Measurement & Matter

Particle Diagrams

• Element Examples: Mg, H₂
• Compound Example: HF
• Mixture Example: Mg & Zn & NaCl

Filtration & Distillation

• Filtration: Separates insoluble solid from liquid (e.g., sand from saltwater)
• Distillation: Separates liquids based on boiling points

Phases of Matter

• Processes: Melting, Freezing, Boiling, Condensing
• Sublimation & Deposition: CO₂(s) ↔ CO₂(g)
• Endothermic vs. Exothermic: Adding vs. removing heat

Physical vs. Chemical Change

• Physical Change: No change in chemical properties (e.g., phase changes, cutting)
• Chemical Change: New substance forms (e.g., burning, rusting)

Significant Figures

• Start counting at first nonzero digit
• Zeros between nonzero digits are significant
• Trailing zeros are significant if a decimal point is present

Rounding

• Addition/Subtraction: Round to least precise place value
• Multiplication/Division: Round to least number of sig figs

Unit & Temperature Conversions

• Conversion between milli-, base, kilo- units
• Temperature (e.g., 0°C = 273 K)
• Example: 150 K = -123°C

Density & Percent Error

• Density: Mass/Volume (refer to reference table)
• Percent Error: Comparison of experimental vs. accepted values

Unit 3: Moles, Stoichiometry, Naming and Formula Writing

Chemical Formulas

• Counting Atoms: Coefficient and subscript

Molar Mass & Calculating Moles

• Mass of one mole = gram formula mass (GFM)
• Example GFM: NaCl = 58.5 g/mol

Types of Reactions

• Synthesis: A + B → AB
• Decomposition: AB → A + B
• Single & Double Replacement: Redox and neutralization reactions

Mole Ratios & Conservation of Mass

• Examples in chemical equations

Balancing Reactions

• Balance by considering polyatomics together

Molecular to Empirical Formulas

• Convert using greatest common factor

Percent Composition & Naming Compounds

• Calculate by mass
• Naming conventions for binary and tertiary compounds

Unit 4: Atomics

Atomic Theory & Models

• Development from solid sphere to wave mechanical model
• Thomson vs. Rutherford's discoveries

Subatomic Particles

• Calculating protons, neutrons, and electrons
• Atomic mass and isotopes

Electron Configurations

• Ground vs. excited state
• Production of light

Lewis Dot Diagrams

• Representation for atoms and ions

Unit 5: Periodic Table

Organization of the Periodic Table

• Mendeleev and Mosley's contributions
• Periods and groups

Properties of Elements

• Metals, nonmetals, and metalloids
• Trends: Atomic radius, electronegativity, ionization energy

Unit 6: Bonding

Bond Types

• Ionic, covalent, metallic
• Octet rule and bond energy

Lewis Dot Diagrams for Bonds

• Representing ionic and covalent bonds

Molecular Polarity

• Polar vs. nonpolar molecules
• Intermolecular forces: Hydrogen bonding

Unit 7: Heat

Heat Flow and Specific Heat

• Heat flows hot to cold
• Specific heat concept and related calculations

Heating vs. Cooling Curve

• Kinetic vs. potential energy changes

Calculating Heat

• Use formulas for temperature changes and phase changes
• Example calculations for heating and phase changes