Chemistry Flashcards: States of Matter & Ions

Chemical Terminology

• Ion: A charged molecule, can be either positive or negative.
• Cation: A positively charged ion.
• Anion: A negatively charged ion.

States of Matter

• Solid: Has a definite shape and volume.
• Liquid: Has a definite volume but takes the shape of its container.
• Gas: Lacks definite shape and volume, fills any available space.
• Plasma: A state of matter where atoms are ionized, leading to free electrons and light emission.

Mixtures and Solutions

• Solution: Composed of a solute dissolved in a solvent.
• Heterogeneous Mixture: Contains unevenly distributed components, e.g., salad dressing.
• Homogeneous Mixture: Uniform throughout, like lemonade made from minute amounts.
• Colloid: A heterogeneous mixture where particles do not settle, e.g., milk.
• Suspension: A heterogeneous mixture with visible particles that settle over time.

Chemical Reactions

• Synthesis: A reaction where two or more reactants combine to form one product, represented as A + B → AB.
• Decomposition: A reaction where one compound breaks down into two or more products, represented as AB → A + B.
• Single Displacement: A reaction where one element replaces another in a compound, represented as AB + C → AC + B.
• Double Displacement: A reaction involving the exchange of elements between two compounds, represented as AB + CD → AD + BC.
• Combustion: A reaction of fuel with oxygen producing water and carbon dioxide, represented as Fuel + O₂ → H₂O + CO₂.

Periodic Table Insights

• Mendeleev: Founder of the periodic table, organized elements by atomic mass.
• Groups: Vertical columns in the periodic table, defining similar properties among elements.
• Periods: Horizontal rows indicating increasing atomic number.

Element Categories

• Alkaline Metals: Group 1, known for softness, reactivity, and low density.
• Alkaline Earth Metals: Group 2, slightly less reactive than Group 1, also low density.
• Transition Metals: Groups 3-12, predominantly harder, typically form +2 ions, and are less reactive.
• Halogens: Group 17, highly reactive nonmetals, exist as diatomic molecules.
• Noble Gases: Group 18, chemically inert due to full valence shells.

Physical and Chemical Properties

• Metals: Found left of the stair step on the periodic table, characterized by luster, malleability, ductility, good conductivity, high density, and a propensity to lose electrons.
• Nonmetals: Located right of the stair step, marked by poor conductivity, brittleness, non-malleability, low density, and a tendency to gain electrons.
• Metalloids: Elements found along the stair step, possessing properties intermediate between metals and nonmetals.

Atomic Theory and Discoveries

• Dalton's Atomic Theory: Asserts that atoms are indivisible, identical for the same element, different for different elements, and maintain constant mass ratios in compounds.
• Thomson: Discovered the electron using a cathode ray tube; proposed the plum pudding model.
• Rutherford: Conducted the gold foil experiment, leading to the discovery of the atomic nucleus.
• Bohr: Developed the planetary model of the atom through experiments with hydrogen.

Chemical Bonds

• Compound: A substance formed from two or more different atoms bonded together.
• Covalent Bonds: Involve sharing of electrons to fill outer electron shells.
• Ionic Bonds: Result from the transfer of electrons, leading to charged ions that attract each other.

Molecular Prefixes

• Mono: 1 (used for oxygen only).
• Di: 2.
• Tri: 3.
• Tetra: 4.
• Penta: 5.
• Hexa: 6.
• Hepta: 7.
• Octa: 8.
• Nona: 9.
• Deca: 10.

Molecular Concepts

• Polar Molecule: Exhibits an asymmetrical charge distribution leading to slight charges at opposite ends due to electronegativity.
• Electronegativity: Measures an atom's ability to attract electrons.
• Hydrate: A compound that includes water molecules integrated into its structure.

Changes and Properties

• Chemical Property: A trait that indicates how a substance may change chemically, e.g., flammability.
• Chemical Change: Occurs when substances react to form new products.
• Physical Property: Observable characteristics such as size, color, and phase that do not alter the substance's chemical identity.