Chapter2F24_GenChem

Page 1: Announcements

• Attendance Code: 2778

• Next Class Preparation:

  • Actively read Chapters 2.3 and 3.6.

  • Watch required pre-recorded videos (Week 2).

  • Complete the Weekly Quiz on Aktiv Chemistry (due Wednesday).

  • No class on Monday (long weekend).

  • Check Lab syllabus and Blackboard; Labs on Tuesday and Thursday.

Page 2: The Scientific Method

• Process of Discovery:

  • Observe and identify a problem.

  • Perform research.

  • Develop question and testable hypothesis.

  • Create method of analysis and make predictions.

  • Conduct experiments multiple times.

  • Interpret and analyze data, then draw conclusions.

  • Theory Development:

    • A tested and supported hypothesis, not "proven."

    • Einstein's quote: "A single experiment can prove me wrong."

Page 3: Scientific Observations

• Observation and Curiosity:

  • Constant observations lead to the formation of laws.

  • Hypothesis testing contributes to knowledge.

  • Experimentation:

    • More experiments lead to hypothesis refinement and theory development.

Page 4: Chemistry Texts

• Reading Assignments:

  • Chemistry: Atoms First 2e, Chapter 2 (Atoms, Molecules, and Ions).

  • Practice with OpenStax UCONN Chem - Atoms First.

Page 5: Historical Foundations in Chemistry

• Matter Inquiry:

  • Debate: Is matter continuous or indivisible?

  • Key Figures:

    • John Dalton (atomic theory).

    • Boyle: Element and compound definitions.

    • Priestly and Lavoisier: Law of Mass Conservation.

    • Proust: Law of Definite Proportions.

    • Law of Multiple Proportions.

Page 6: Mass Ratios and Calculations

• Calculations:

  1. Simplest whole number mass ratios of compounds (e.g., H2O, H2O2).

  2. Oxygen amount in carbon combustion.

  3. C to O mass ratio calculations for two CO compounds.

Page 7: Dalton's Atomic Theory

• Atomic Composition:

  • Matter = tiny particles called atoms.

  • Elements consist of one type of atom.

  • Atoms differ among elements in properties.

  • Compounds formed by atoms of multiple elements.

  • Atoms rearranged but neither created nor destroyed.

Page 8: More Chemistry Reading

• Reading Assignments:

  • Chemistry: Atoms First 2e, Chapters 2.2-2.3.

Page 9: Atomic Structure

• Nucleus and Electron Cloud:

  • Nucleus: Protons (+), Neutrons (neutral).

  • Accounts for most mass: Mass # = Atomic # + Neutrons.

  • Electron cloud contains electrons (-), defines overall charge.

Page 10: Atomic Identity

• Atom Characteristics:

  • Atoms are neutral, differ by atomic number (Z, protons).

  • Organized in the periodic table (e.g., Carbon, Nitrogen).

Page 11: Isotopes

• Definition:

  • Atoms with the same Z but different mass numbers (A).

  • Isotopes retain chemical properties; differ in mass.

Page 12: Atomic Weight

• Periodic Table:

  • Atomic weight = average atom mass (amu).

  • Weight derived from natural isotope abundances.

Page 13: Atomic Nucleus

• Nucleus Positioning:

  • Small, positively charged nucleus occupies minimal atom volume.

Page 14: Nucleus vs. Atom Volume

• Volume Comparison:

  • Nucleus (10^-15 m) vs. Atom (10^-10 m).

Page 15: Electrons

• Electron Properties:

  • Negatively charged, light, repel one another.

  • Form outer boundary of atom, influence interaction.

Page 16-17: Discoveries Related to Electrons

• Thomson's and Millikan's Experiments:

  • Thomson: Cathode rays are electrons.

  • Millikan: Determined individual electron charge and mass.

Page 18-19: Class Announcements

• Attendance Code: 5978

• Prepare for Class: Read Chapter 2.4.

• Daily Quiz on Aktiv Chemistry by 8 AM (before class).

• Must rework assignments before Tests 1A & 1B.

Page 20-22: Practice Assignments

• Rework questions in various math categories (multiplication, fractions, etc.).

• Neutral atoms charge balancing concepts (ions, cations, anions).

Page 23: Subatomic Particles Summary

• Primary Particles Comparison:

  • Electron, Proton, Neutron: Charge, weight, and mass presentation.

Page 24: Atomic Mass Calculation

• Example with Helium:

  • Various isotopes of He with calculations for atomic mass.

Page 25: Practice Problems

• Subatomic Particles Count:

  • Given isotopes, determine subatomic particle counts.

  • Weighted average calculations for atomic mass.

Page 26-29: Significant Figures Practice

• Practice Calculation Examples:

  • Counting significant figures in value sets.

Page 30-36: Rules and Practice on Significant Figures

• Significant Figures Rules Explained:

  • Non-zero numbers, zero placement in numbers, and calculations.

Page 37-39: Practice Problems

• Atomic Mass & Mole conversions practice.

Page 40: Class Expectations for Exam 1A

• Attendance Code: 7395

• Review material for exam structure and preparation.

Page 41-57: Practice and Understanding of Molar Mass and Mole Concept

• Various practice assignments on molecular masses and conversions.

Page 58-59: Isomer Examples

• Outline differences in structural isomers with shared molecular formulas.