Chem 110

Energy and Chemical Processes

Page 1: Energy Basics

• Definition of Energy

  • Ability to do work, quantifiable in various units.

• Units of Energy

  • Joules (SI unit)

  • Calories (used in health professions)

• Law of Conservation of Energy

  • Energy cannot be created or destroyed; it can only change forms.

• System and Surroundings

  • System: the part of the universe being studied.

  • Surroundings: everything outside the system.

  • Energy exchange occurs between the system and surroundings.

Page 2: Temperature and Heat

• Temperature

  • Measure of thermal energy, measured in three scales:

    • Fahrenheit: Freezes at 32°F, boils at 212°F.

    • Celsius: Freezes at 0°C, boils at 100°C.

    • Kelvin: Absolute zero is 0 K.

• Heat

  • Transfer of energy, proportional to mass and temperature change.

  • Positive ΔT indicates energy input; negative ΔT indicates energy output.

Page 3: Energy Changes in Chemical Reactions

• Energy Changes

  • Chemical reactions involve energy changes.

  • Exothermic Reactions: Energy is released.

  • Endothermic Reactions: Energy is absorbed.

• Heat Equation: ( q = m \cdot C \cdot \Delta T )

Page 4: Matter

• Definition of Matter

  • Anything with mass and volume.

• Composition of Matter

  • Composed of atoms and molecules.

• Classification of Matter

  • Phases: Solid, liquid, gas.

  • Composition: Pure substances or mixtures.

Page 5: Properties of Matter

• Physical Properties

  • Can be observed without changing the substance (e.g., mass, volume).

• Chemical Properties

  • Describe how a substance changes (e.g., reactivity).

• Law of Conservation of Mass

  • Matter is not created or destroyed in chemical reactions.

Page 8: Atoms and Elements

• Elements

  • Composed of one type of atom, cannot be broken down.

• Atoms

  • Smallest stable unit of matter, composed of protons, neutrons, and electrons.

• Periodic Table

  • Organized by atomic number; provides information about elements.

Page 10: Ions

• Ions

  • Atoms that gain or lose electrons to achieve stability.

  • Cations: Positively charged (lose electrons).

  • Anions: Negatively charged (gain electrons).

Page 13: Compounds

• Definition of Compounds

  • Substances formed from two or more elements in fixed proportions.

• Types of Compounds

  • Ionic: Formed from cations and anions.

  • Molecular: Formed from nonmetals sharing electrons.

Page 14: Ionic Bonding

• Ionic Bonds

  • Formed through the transfer of electrons between metals and nonmetals.

• Ionic Compounds

  • Composed of cations and anions, overall neutral charge.

Page 16: Molecular Mass

• Molecular Mass Calculation

  • Sum of atomic masses of all atoms in a compound.

Page 20: Characteristics of Molecules

• Covalent Bonds

  • Formed by sharing electrons; can be polar or nonpolar.

• Polarity

  • Determined by electronegativity differences between atoms.

Page 25: Measurements

• Scientific Measurement

  • Reported as a quantity and a unit.

• Significant Figures

  • Important for accuracy in measurements.

Page 31: Moles

• Mole Concept

  • Avogadro's number: ( 1 \text{ mole} = 6.022 \times 10^{23} ) particles.

• Molar Mass

  • Mass of one mole of a substance.

Page 34: Chemical Reactions

• Evidence of Chemical Reactions

  • Color change, gas formation, solid formation, light emission.

• Chemical Equations

  • Represent reactants and products in a reaction.

Page 38: Stoichiometry

• Stoichiometry

  • Study of quantitative relationships in chemical reactions.

• Limiting Reactant

  • Reactant that produces the least amount of product.

Page 42: Gas Laws

• Kinetic Theory of Gases

  • Gases consist of particles in constant motion.

• Gas Laws

  • Boyle's Law, Charles' Law, and Ideal Gas Law relate pressure, volume, and temperature.

Page 45: Intermolecular Forces

• Intermolecular Forces (IMF)

  • Forces between molecules that affect physical properties.

• Types of IMF

  • London Dispersion Forces, Dipole-Dipole Interactions, Hydrogen Bonds.

Page 51: Solutions

• Solutions

  • Homogeneous mixtures of solute and solvent.

• Solubility

  • Maximum amount of solute that can dissolve in a solvent.

Page 56: Acids and Bases

• Acids and Bases

  • Acids produce H⁺ ions; bases produce OH⁻ ions.

• pH Scale

  • Measures the concentration of hydronium ions in a solution.

Page 58: Carbohydrates and Lipids

• Carbohydrates

  • Sugars and starches, important for energy.

• Lipids

  • Fats and oils, primary source of long-term energy.

This note summarizes the key concepts from the provided transcript, organized by topic and page