Achievement Test

• Chemistry: The study of matter, its composition, properties, and changes.
• Matter: Anything that has mass and occupies space, essentially anything physically real.
• Chemistry lies in the middle of the relationships between major branches of science, emphasizing its importance
• Biochemistry is a field where biologists and chemists work together, showing overlap between biology and chemistry
• Geochemistry is a field where geology and chemistry intersect, demonstrating overlap between these two disciplines
• Chemistry is referred to as the "central science" as it links various fields of science together through their dependence on matter
• Kinetic Molecular Theory of Matter:

  • Describes the microscopic properties of atoms or molecules and their interactions
  • Leads to observable macroscopic properties like pressure, volume, and temperature
• Phases of Matter:

  • Matter can exist in different states: solid, liquid, and gas
  • Explained by the Kinetic Molecular Theory
• Phase Changes:

  • Transitions matter can undergo from one phase to another
  • Elucidated by the Kinetic Molecular Theory
• Kinetic molecular theory of matter: Matter is made up of particles that are constantly moving
• Energy: All particles have energy, but the energy varies depending on the temperature the sample of matter is in
• Temperature: The temperature of a substance is a measure of the average kinetic energy of the particles
• Phase: A change in phase may occur when the energy of the particles is changed
• Spaces: There are spaces between particles of matter
• Intermolecular forces: There are attractive forces between atoms/molecules, and these become stronger as the particles move closer together. These attractive forces are called intermolecular forces
• Gas shape and volume conform to the shape of the container
• Gas properties include high compressibility and high ability to flow
• Gas Properties: Compressibility (High), Ability to flow (High)
• Liquid conforms to the shape of the container; volume limited by surface
• Liquid has compressibility (Very low) and the ability to flow (Moderate)
• 1. Solid: Maintains its own shape and volume
• Properties: Compressibility (Almost none)
• Melting (or fusion) is the process of a solid turning into a liquid
• Vaporization is the transformation of a liquid into a gas, which can occur through boiling or evaporation
• Condensation is the change of a gas into a liquid
• Freezing (or solidification) is the transition of a liquid into a solid state
• Deposition is the conversion of a gas directly into a solid without passing through the liquid phase
• Sublimation is the process of a solid turning directly into a gas without becoming a liquid first
• Molecules: Units that interact to form an assembly.
• Intermolecular Forces: Forces that are interrelated by assembly.
• Van der Waals Forces:

  • Intermolecular forces including LDF, attraction, and repulsions between atoms, molecules, and surfaces
• Dipole-dipole interactions:

  • Attraction between partial charges in different molecules, aligning positive and negative ends
• London dispersion force:

  • Temporary attractive force due to temporary dipoles in adjacent atoms, also known as induced dipole-induced dipole attraction
• Polar vs. Nonpolar Molecules:

  • Polar molecules have an electronegativity difference
  • Nonpolar molecules share electrons equally or cancel polar bonds
• Hydrogen Bonding:

  • Attractive force between hydrogen and electronegative atoms like oxygen, nitrogen, or fluorine in different molecules
• Ionic interactions are between charged atoms or molecules called ions
• Positively charged ions are cations, such as Na(+), Li(+), and Ca(2+)
• Negatively charged ions are anions, such as Cl(-), Br(-), and HO(-)
• Coulomb's Law describes the attractive forces between oppositely charged ions
• The force increases with charge and decreases as the distance between ions increases