Chemistry Module 1

Module 1

• Chemistry: The study of matter and its changes, including organic, inorganic, physical, analytical, and biochemistry.

• Matter: Anything that takes up space.

• Mass: A measurement of the amount of matter.

• Science: Using evidence to develop testable explanations of natural phenomena.

• Hypothesis: A testable expectation or prediction of a phenomena.

• Theory: An explanation of a phenomena based on observations. It can be modified as new evidence arises.

• Scientific Law: A relationship in nature supported by human experiments.

• Pure Research: Aims to expand knowledge.

• Applied Research: Focuses on solving specific problems.

• Model: A visual or verbal explanation of data.

• Units: A system of measurements.

• Base Units: A system of fundamental measurements.

• Derived Units: Units derived from the combination of base units. (e.g., meters per second).

• Weight: A measure of the amount of matter and the gravitational force exerted on an object.

• Time: Measured in seconds.

• Length: Measured in meters.

• Mass: Measured in kilograms.

• Temperature: Measured in Kelvin.

• Volume: The space occupied by an object, measured in liters.

Module 2

• Density: Mass per unit volume (mass/volume).
• Physical Properties: Properties observed without altering a substance (e.g., color, odor, density, mass, solubility, state, melting point, boiling point).
• Chemical Properties: Properties observed when a substance undergoes a chemical change (e.g., reactivity, flammability, acidity/basicity, chemical composition).
• States of Matter:
  • Solids: Have a fixed shape and volume. Particles are tightly packed.
  • Liquids: Have a definite volume but take the shape of their container. Particles move past each other.
  • Gases: Have no fixed shape or volume; they take the shape and volume of their container. Particles are widely dispersed.
  • Plasma: A highly energized ionized gas.

Module 3

• Element: A pure substance that cannot be broken down into simpler substances by physical or chemical means.

• Periodic Table: A table that organizes elements based on their atomic number and recurring chemical properties. Elements are arranged in horizontal rows (periods) and vertical columns (groups).

• Compound: A substance composed of two or more elements chemically combined in a fixed ratio.

• The Law of Definite Proportions: A compound has the same elements in the same proportions by mass, regardless of the sample size.

• The Law of Multiple Proportions: When elements combine to form more than one compound, the ratios of the masses of one element that combine with a fixed mass of the other element will be small whole numbers.

• Mixtures: A combination of two or more substances not chemically bonded,

• Homogenous Mixture: The different substances are evenly mixed and not easily distinguishable (e.g., salt water).

• Heterogeneous Mixture: Different substances are not evenly mixed, and the components are typically visible (e.g., sand and water).

• Separation Techniques: Techniques used to separate substances in mixtures, such as filtration and distillation.

Module 4

• Atomic Theory: Dalton's atomic theory: Elements are composed of extremely small particles called atoms, atoms of a given element are identical, atoms of different elements have different properties, in chemical reactions, atoms are combined, separated, or rearranged to form new substances, atoms cannot be divided, created, or destroyed.

Module 5

• Cathode Rays: Streams of negatively charged particles emitted from a cathode in a vacuum tube (later identified as electrons).
• Plum Pudding Model (Thomson): Atoms are made up of a positively charged sphere with negatively charged electrons embedded within it, like "plums in a pudding".
• Rutherford's Gold Foil Experiment: Aimed at testing the plum pudding model. Showed, that atoms have a small, dense, positively charged nucleus at their center with negative electrons surrounding it in a largely empty space.
• Rutherford's Nuclear Model: Atoms have a dense, positively charged nucleus containing most of the mass, with electrons orbiting the nucleus.
• Alpha Particles: Particles consisting of two protons and two neutrons with a positive charge.
• Helium Nucleus: Essentially an alpha particle.

Module 6

• Bonding: Atoms form compounds by interacting in order to become more stable

• Ionic Bonds: Electrons are transferred from one atom to another, forming positive and negative ions that are attracted to each other.

• Covalent Bonds: Atoms share electrons to achieve a stable electron configuration.

• Lewis Structures: Diagrams that show the arrangement of atoms and their bonds in a molecule.

Module 7

• Bond Energy: The energy required to break or form a chemical bond.

• Covalent Bond Stability: Bonds formed between atoms in order to attain a more stable electron configuration.

• Atomic Orbitals: Regions in an atom where electrons are most likely to be found.

• Quantum Numbers: Numbers that describe the properties of atomic orbitals.

Module 8 (Questions)

• Periodic Law: The properties of elements are periodic functions of their atomic numbers.

• Intensive Properties: Properties that are independent of the amount of matter (e.g., density, melting point, boiling point).

• Extensive Properties: Properties that depend on the amount of matter (e.g., mass, volume, amount of energy).

• Atom: The smallest unit of an element that maintains its chemical identity.

• Electron Configuration: The arrangement of electrons in an atom.

• Quantum: The minimum amount of energy a photon can have or be absorbed by an electron.

• Periodic Groups: Columns of elements organized in the periodic table that share similar properties.

• Periods: Rows of elements organized in the periodic table. Elements on a period share increasing atomic numbers.

• Electron Affinity: The ability of an atom to accept an electron.

• Electronegativity: The ability of an atom to attract electrons in a chemical bond.

• Metallic Character: Tendency of an element to lose electrons.

• Radioactive Elements: elements that decay by emitting radioactive particles.

• Unstable Elements: Elements that decay and change over time.

• Chemical Bond: The force of attraction that holds two or more atoms together. (28)

• Distillation: Separation technique of substances with different boiling points based on their phase changes (liquids to gases).

• Filtration: Separation technique using a barrier that allows liquids to pass through but traps solids (e.g., through a filter paper).

• Homogenous Mixtures: Solutions that have uniform composition throughout (e.g., salt water).

• Heterogeneous Mixtures: Mixtures where the components are not uniformly spread out (e.g., sand and water).

• Polyatomic ions: A set of several atoms that act as a single unit (e.g., SO42- or hydroxide ion).