BIOL-2401 Basic Chemistry Comprehensive Study Guide

Vocabulary flashcards covering atomic structure, chemical bonds, polarity, water properties, mixtures, and acid-base chemistry from BIOL-2401 Basic Chemistry.

Matter

Anything that has mass and occupies space.

Atom

The structural unit of an element, consisting of a nucleus with protons and neutrons surrounded by electrons.

Element

A fundamental chemical substance that cannot be broken down into simpler substances.

Proton

A subatomic particle carrying a positive electrical charge that is located in the nucleus of an atom.

Neutron

A subatomic particle carrying a neutral charge (no charge) that is located in the nucleus of an atom.

Electron

A subatomic particle carrying a negative electrical charge that orbits around the atomic nucleus.

Isotope

Structural variations of an element whose atoms have the same number of protons but a different number of neutrons.

Radioisotope

An unstable isotope that undergoes radioactive decay; iodine-123 is a radioisotope useful in medical imaging.

Valence Shell

An atom's outermost electron shell, containing valence electrons that determine the atom's chemical reactivity and stability.

Octet Rule

The chemical principle stating that atoms interact in order to achieve a full valence shell containing 8 electrons for maximum chemical stability.

Ion

A charged particle formed when an atom gains or loses one or more valence electrons.

Cation

A positively charged ion produced when an atom loses valence electrons.

Anion

A negatively charged ion produced when an atom gains valence electrons.

Ionic Bond

A chemical bond formed when valence electrons are transferred from one atom to another, resulting in oppositely charged ions held together by electrostatic attraction.

Covalent Bond

A chemical bond formed when two atoms share pairs of valence electrons.

Nonpolar Covalent Bond

A covalent bond in which valence electrons are shared equally between atoms because there is no difference in electronegativity, producing no partial charges.

Polar Covalent Bond

A covalent bond in which valence electrons are shared unequally due to electronegativity differences, resulting in partial positive and partial negative charges.

Electronegativity

The relative ability of an atom to attract shared electrons toward itself in a chemical bond.

Hydrogen Bond

A weak attraction between a partially positive hydrogen atom in one polar molecule and a partially negative atom in another molecule.

Solvent

The dissolving medium in a solution, such as water, that dissolves solutes.

Hydrophilic

Refers to polar or charged substances that are water-loving and readily dissolve in or interact with water.

Hydrophobic

Refers to nonpolar substances that are water-fearing and do not dissolve in or mix with water.

Amphipathic

Refers to a molecule that possesses both polar (hydrophilic) and nonpolar (hydrophobic) parts.

Electrolyte

A substance that dissociates into ions in water and is capable of conducting an electrical current.

Solution

A homogeneous mixture containing very small solute particles that do not settle out and do not scatter light.

Colloid

A mixture with intermediate particle size where particles do not settle out but are large enough to scatter light.

Suspension

A heterogeneous mixture with large solute particles that settle out over time if not constantly mixed.

Acid

A substance that increases the $H^+$ concentration in solution, lowering the $pH$ to a general range below 7.

Base

A substance that decreases the $H^+$ concentration in solution, raising the $pH$ to a general range above 7.

Buffer

A chemical system that stabilizes $pH$ by binding $H^+$ when $H^+$ concentration increases and releasing $H^+$ when $H^+$ concentration decreases.