The Chemistry of Life: Part 1 - Interactions of Atoms

Vocabulary practice flashcards covering fundamental chemistry terms, subatomic structure, chemical bonding, biological elements, electrolytes, solutions, molarity, and pH buffers based on the lecture notes.

Chemistry

The science of the structure and interactions of elemental matter.

Matter

Anything that occupies space and has mass, existing as a solid, liquid, or gas.

Mass

The energy contained in an object at rest, defined by $E = mc^2$.

Weight

The force of gravity acting on matter, which varies based on gravitational changes.

Fundamental Particles

The three basic building blocks of all matter: electrons, up quarks, and down quarks.

Atom

The smallest unit of matter that retains the unique properties and characteristics of an element.

Proton

A subatomic particle in the nucleus of an atom with a charge of $+1$ and a mass of $1\,amu$.

Neutron

A subatomic particle located in the atomic nucleus with a charge of $0$ and a mass of $1\,amu$.

Electron

A subatomic particle orbiting the nucleus with a charge of $-1$ and a mass of approximately $0$ (about 2000 times lighter than a proton).

Atomic Number

The total number of protons present in the nucleus of an atom.

Atomic Mass

The sum of the number of protons and the number of neutrons in an atom.

Valence Shell

The outermost electron shell of an atom.

Octet Rule

The principle that valence electrons participate in chemical reactions to bring the total number of valence electrons in the outer shell to $8$ (or $2$ if the atom has only $1$ shell).

Inert Elements

Elements that have a completely filled valence shell and do not participate in chemical reactions.

Reactive Elements

Elements with an incomplete valence shell that participate in chemical reactions.

Isotopes

Varieties of an element that differ from one another only in their number of neutrons and atomic mass, while sharing identical chemical properties.

Relative Atomic Mass

A calculated mass that accounts for the average atomic masses of all naturally occurring isotopes of an element.

Ionization

The transfer of electrons from one atom to another, creating charged atoms called ions.

Anion

A negatively charged ion formed when an atom gains electrons, resulting in more electrons than protons.

Cation

A positively charged ion formed when an atom donates electrons, resulting in more protons than electrons.

Electrolytes

Substances that ionize in solution and can conduct an electrical current.

Sodium ion ($Na^+$)

The most abundant extracellular cation, essential for nerve and muscle signaling as well as osmotic water movement.

Potassium ion ($K^+$)

The most abundant intracellular cation, required for proper nerve and muscle signaling.

Calcium ion ($Ca^{2+}$)

An essential cation involved in bone and teeth hardness, muscle contraction, and neurotransmitter release.

Molecule

A particle formed by two or more atoms held together by chemical bonds.

Compound

A molecule composed of two or more different elements.

Molecular Formula

A chemical representation identifying the exact type and quantity of each element in a molecule.

Structural Formula

A diagrammatic representation showing the spatial location and arrangement of each atom within a molecule.

Isomers

Molecules that share the exact same molecular formula but have different structural formulas and physical arrangements.

Molecular Weight

The sum of the individual atomic weights of all atoms in a compound.

Ionic Bond

A chemical bond formed by the electrostatic attraction between a cation and an anion.

Nonpolar Covalent Bond

The strongest chemical bond, formed when shared electrons spend an approximately equal amount of time around each nucleus.

Polar Covalent Bond

A covalent bond formed when shared electrons spend more time orbiting one nucleus than another, producing distinct positive and negative regions.

Hydrogen Bond

A weak attraction between a slightly positive hydrogen atom in one molecule and a slightly negative oxygen or nitrogen atom in another molecule.

Solvency

The ability of a substance, such as water, to dissolve other chemicals.

Hydrophilic

Properties of substances that are polarized or charged and readily dissolve in water.

Hydrophobic

Properties of non-polar or neutral substances that do not dissolve in water.

Hydration Spheres

Clusters of water molecules that surround individual ions when ionic bonds break, preventing them from re-associating.

Adhesion

The tendency of one chemical substance to cling to a different substance.

Cohesion

The tendency of identical molecules to cling to one another.

Surface Tension

A cohesive force at the surface of water produced by the collective strength of its hydrogen bonds.

Mole

An amount of a compound in grams equal to its molecular weight, containing $6.023 \times 10^{23}$ units of that substance.

Avogadro's Number

The constant value $6.023 \times 10^{23}$, representing the number of particles present in $1\,mole$ of a substance.

Molarity ($M$)

A measure of concentration defined as the number of moles of solute dissolved per liter of total solution.

Acid

A molecule that acts as a proton donor by releasing hydrogen ions ($H^+$) in water.

Base

A molecule that acts as a proton acceptor by binding free hydrogen ions ($H^+$).

Buffer

A chemical system that resists changes in pH by accepting or releasing hydrogen ions ($H^+$).

Carbonic Acid-Bicarbonate System

A buffer system in which $H_2CO_3$ donates $H^+$ during a rise in pH, and $HCO_3^-$ accepts $H^+$ during a drop in pH.