Honors Physical Science Nine Weeks Test Review

Honors Physical Science Nine Weeks Test Review

States of Matter

• Characteristics of Solids, Liquids, and Gases:
  • Solid: Definite shape and volume.
  • Liquid: Definite volume, but no definite shape; takes the shape of its container.
  • Gas: No definite shape or volume; expands to fill available space.
• Plasma:
  • Most common state of matter in the universe.
  • Mentioned in the context alongside solids, liquids, and gases.

Changes of State

• Melting:
  • The process of changing a solid into a liquid.
  • Requires energy/heat.
• Boiling:
  • The process of changing a liquid into a gas.
  • Requires energy/heat.
• Heat of Fusion/Vaporization:
  • Fusion: Amount of energy needed to melt a solid.
  • Vaporization: Amount of energy needed to vaporize a liquid.

Matter Classification

• Element: A pure substance consisting of only one type of atom.
• Compound: A substance formed when two or more elements are chemically bonded.
• Mixture: A combination of two or more substances that are physically combined.

Kinetic Molecular Theory

• Kinetic Molecular Theory:
  • Particles are always in motion.
  • More energy implies faster motion of particles.

Mixtures

• Mixtures:
  • Can involve solids, liquids, and gases.
  • Solutions are homogeneous mixtures.

Properties and Changes

• Chemical Properties: Describe how a substance changes into a new substance (e.g., flammability, reactivity).
• Physical Properties: Characteristics that can be observed or measured without changing the substance's composition (e.g., color, odor, solubility, conductivity).
• Physical Change: Affects physical properties only; does not create a new substance.
• Chemical Change: Results in the formation of new substances.

Solutions

• Solute:
  • The substance that is dissolved in a solution.
• Solvent:
  • The substance that does the dissolving in a solution.
• Factors Affecting Dissolving Rate:
  • Stirring.
  • Heating.
  • Particle size/surface area.
• Types of Solutions:
  • Saturated: Contains the maximum amount of solute that can dissolve in a given amount of solvent at a specific temperature.
  • Supersaturated: Contains more than the maximum amount of solute that can dissolve; unstable.
  • Unsaturated: Contains less than the maximum amount of solute that can dissolve.
• Temperature:
  • A measure of the average kinetic energy (KE) of the particles in a substance.

Tyndall Effect

• Tyndall Effect:
  • The scattering of light by a mixture; used to distinguish between solutions and colloids.

Water as a Solvent

• Water as a Good Solvent:
  • Water is polar and can break ionic bonds, allowing ionic compounds to dissolve.

Phase Changes

• Evaporation:
  • Liquid to gas.
• Sublimation:
  • Solid to gas.
• Deposition:
  • Gas to solid.

Colloids

• Colloid Examples:
  • Milk
  • Fog, gas in liquid
  • Liquid in gas.
  • Solid in solid

Viscosity

• Examples of Viscous Liquids:
  • Syrup

Law of Conservation of Mass

• Law of Conservation of Mass:
  • Matter cannot be created or destroyed in chemical reactions. Mass is conserved.

Chemical Bonds

• Ionic Compounds:
  • Involve the transfer of electrons between a metal and a nonmetal.
• Covalent Compounds:
  • Involve the sharing of electrons between two or more nonmetals.
• Ions:
  • Metals lose electrons to become cations (+). Nonmetals gain electrons to become anions (-).
• Cation/Anion:
  • Metal/Nonmetal
• Charges of Ions Based on Groups:
  • Group 1: +1
  • Group 2: +2
  • Group 17: -1
• Diatomic Elements:
  • Elements that exist as two atoms bonded together in their natural state (e.g., H2, N2, O2, F2, Cl2, I2, Br_2). Show how electrons are shared in diatomic elements.
• Valence Electrons:
  • Electrons in the outermost energy level of an atom.
• Octet Rule:
  • Atoms gain, lose, or share electrons to achieve a stable electron configuration with 8 valence electrons in their outer shell.
• Covalent Bonds Form Molecules:
  • Substances that contain ionic bonds are usually solid with high melting point.
• Single, Double, and Triple Bonds:
  • Represent the number of shared electron pairs between atoms (1, 2, or 3).
• Polyatomic Ion:
  • Ions made of multiple atoms.

Chemical Reactions

• Naming Ionic Compounds:
  • Know how to name ionic compounds.
• Reactants/Products:
  • Reactants are the starting materials in a chemical reaction; products are the substances formed.
• Coefficients:
  • Numbers in front of chemical formulas in a balanced equation that indicate the relative amounts of reactants and products.
• Catalysts:
  • Substances that speed up a reaction without being consumed.
• Combustion:
  • A chemical process that involves rapid reaction between a substance with an oxidant, usually oxygen, to produce heat and light.
• Exergonic Reactions:
  • Release energy.
• Endergonic Reactions:
  • Absorb energy.
• Exothermic Reactions:
  • Release heat.
• Endothermic Reactions:
  • Absorb heat.
• Symbols in Chemical Equations:
  • (s) - solid
  • (l) - liquid
  • (g) - gas
  • (aq) - dissolved in water (aqueous)
• Types of Reactions:
  • Synthesis, decomposition, single replacement, double replacement, combustion.

Indicators of Chemical Reactions

• Indicators of a Chemical Reaction:
  • Color change
  • Temperature change
  • Gas production
  • Precipitate formation
• Counting Atoms in Equations:
  • Use subscripts and coefficients to count atoms.
• Balancing Chemical Equations:
  • Ensuring the number of atoms of each element is the same on both sides of the equation.
• Precipitate:
  • A solid formed from solution during a chemical reaction.

Atomic Structure

• Atomic Number:
  • The number of protons in an atom's nucleus.
• Elements in a Group:
  • Similar number of valence electrons -> similar reactivity.
• Mass Number:
  • The total number of protons and neutrons in an atom's nucleus.
• Relationship between Protons and Electrons:
  • In a neutral atom, the number of protons (+) equals the number of electrons (-).
• Electron Location and Energy:
  • Electrons further from the nucleus have more energy.
• Mass of Atom:
  • Concentrated in the nucleus (protons and neutrons).
• Volume of Atom:
  • Mostly empty space; electrons occupy a larger volume in the electron cloud.
• Isotopes:
  • Atoms of the same element with different numbers of neutrons (different mass numbers).
• Valence Electrons Based on Group:
  • Determined by the group number (e.g., Group 1 has 1 valence electron).
• Number of Electrons in Energy Levels:
  • 1st energy level: 2
  • 2nd energy level: 8
  • 3rd energy level: 18
• Determining Number of Neutrons in an Isotope:
  • Mass number - Atomic number = Number of neutrons
• Unstable Nucleus:
  • Too many protons or neutrons can lead to an unstable nucleus and radioactivity.
• Structure of the Nucleus:
  • Dense, located at the center of the atom, and contains protons and neutrons.

Radioactivity

• Radioactivity Decay:
  • The process by which an unstable atomic nucleus loses energy by emitting radiation.

Periodic Table

• Elements in the Same Period:
  • Same Amount of energy levels
• Location of Transition Metals:
  • In the middle of the periodic table.
• Isotope Notation:
  • Element symbol, mass number: {}_{6}^{14}C
• Location of Metals, Nonmetals, and Metalloids:
  • Metals: left side.
  • Nonmetals: right side.
  • Metalloids: located between metals and nonmetals.
• Names of Groups:
  • Alkali metals, alkaline earth metals, halogens, noble gases.
• Most Reactive Metals and Nonmetals:
  • Metals: lower left.
  • Nonmetals: upper right.