The Chemical Foundation of Life Flashcards

A complete list of vocabulary flashcards based on the lecture notes covering basic chemistry concepts, atomic structure, water properties, pH, and organic carbon molecules.

Matter

Any substance that occupies space and has mass.

Elements

Unique forms of matter with specific chemical and physical properties that cannot be broken down into simpler substances by chemical means.

Atom

The smallest unit of matter that retains all of the element's chemical properties.

Nucleus

The center of an atom where neutrons and protons are located.

Electron Cloud

The region surrounding the nucleus that contains the electrons.

Proton

A subatomic particle located in the nucleus with a positive charge of $+1$ and a mass of $1\,\text{amu}$ that defines each element.

Neutron

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

Electron

A subatomic particle found outside the nucleus in orbitals or cloud with a negative charge of $-1$ and considered to have no mass ($0\,\text{amu}$).

Atomic Number

The distinct number of protons contained within an atom of a specific element.

Atomic Mass

The total mass of an atom calculated as the number of protons plus the number of neutrons, expressed in atomic mass units (amu).

Isotopes

Forms of an element with different numbers of neutrons, and thus different mass numbers.

Bohr Model

An early atomic model featuring protons in the nucleus and electrons in circular orbits at specific distances from the nucleus.

Valence Shell

The outermost electron shell of an atom.

Valence Electrons

Electrons located in the outermost electron shell of an atom.

Octet Rule

The principle that atoms achieve maximum stability when they have a full valence shell ($8$ electrons for most elements, or $2$ electrons for Hydrogen and Helium).

Electron Orbitals

Complex shapes that describe how electrons are spatially distributed around the nucleus.

s Subshell

A spherical subshell containing one electron orbital.

p Subshell

A dumbbell-shaped subshell containing three electron orbitals.

Chemical Bond

The attractive force that links atoms together to form molecules.

Covalent Bonds

Very strong chemical bonds formed when electrons are shared between atoms.

Molecules

Atoms that are held together by covalent bonds.

Non-Polar Covalent Bonds

Covalent bonds characterized by the equal sharing of electrons between atoms.

Polar Covalent Bonds

Covalent bonds characterized by the unequal sharing of electrons between atoms.

Ionic Bonds

The electrostatic charge attractions between positive metal ions and negative non-metal ions; weaker than covalent bonds.

Ionic Compounds

Assemblies of ions held together by ionic bonds.

Reactants

Substances used at the beginning of a chemical reaction, written on the left side of the reaction arrow.

Products

Substances formed at the end of a chemical reaction, written on the right side of the reaction arrow.

Irreversible Reaction

A chemical reaction that proceeds in one direction until all the reactants are used up.

Reversible Reaction

A chemical reaction where reactants are converted to products, but some product can be converted back to reactant.

Hydrogen Bonds

Weak interaction between the slight positive charge ($\delta+$) of hydrogen and the slight negative charge ($\delta-$) of a more electronegative atom on another molecule.

Van der Waals Interactions

Weak attractions or interactions between two or more molecules in close proximity due to changes in electron density.

Hydrophilic

Refers to polar and charged substances that attract or interact well with water ('water loving').

Hydrophobic

Refers to non-polar compounds, such as fats and oils, that do not interact well with water ('water fearing').

Specific Heat Capacity

The amount of heat one gram of a substance must absorb in order to raise its temperature by $1\,^\circ\text{C}$.

Heat of Vaporization

The amount of energy required to change one gram of a liquid substance to a gas.

Solvent

A liquid capable of dissolving other polar molecules and ions (e.g., water).

Solute

The compounds dissolved or mixed in with a solvent.

Cohesion

The attraction of water molecules to each other caused by hydrogen bonding.

Surface Tension

The capacity of a substance to withstand being ruptured when placed under tension or stress.

Adhesion

An attraction between water molecules and other molecules.

Capillary Action

The movement of water through narrow spaces without the assistance of external forces, driven primarily by adhesion and cohesion.

pH Scale

A measurement scale indicating the acidity ($\text{pH} < 7$) or alkalinity ($\text{pH} > 7$) of a solution based on hydrogen ion ($\text{H}^+$) concentration.

Buffer

A solution that can resist changes in pH upon the addition of acidic or basic components.

Hydrocarbons

Organic molecules consisting entirely of carbon and hydrogen.

Isomers

Molecules that have the same chemical formula but differ in placement/arrangement of atoms or types of bonds between atoms.

Structural Isomers

Isomers that have a different covalent arrangement of atoms.

Geometric Isomers

Isomers that have a different arrangement of atoms around a double bond.

Enantiomers

Molecules that share a chemical formula and bonds but differ in 3D placement of atoms as mirror images.

Trans Configuration

A double bond configuration in unsaturated fatty acids where carbons are on opposite sides of the double bond.

Cis Configuration

A double bond configuration in unsaturated fatty acids where carbons are on the same side of the double bond.

Functional Groups

Groups of atoms within a molecule that confer consistent specific properties to those molecules.