Structure of the periodic table reflects electron configuration.

If we draw an analogy between the changes that matter undergoes in chemistry and a dramatic play, the periodic properties of the various atoms would be the personality traits of the actors underlying their motivations.

The periodic table is an arrangement of the chemical elements ordered by atomic number in columns and rows (groups and periods). The design of the periodic table reflects the observation that many properties of the chemical elements are periodic functions of their atomic number. The periodic table is arranged so as to emphasize these periodic properties. In concert with an atom's valence shell configuration, the periodic properties of an element provide you with a thumbnail picture of its tendencies, allowing you to predict how it will behave in different contexts. The periodic properties are atomic radius, ionization energy, electron affinity and electronegativity.

Only rarely to questions appear on the MCAT that ask you directly about periodic properties, but like so many of these early chapters, the material is fundamental to much else which comes later. Of the periodic properties, the electronegativity is especially crucial, although all of them are important. Considering the electronegativity difference between bonded atoms is the first step to assigning bond polarity. Understanding bond polarity is necessary for predicting intermolecular forces, solubility relationships or assigning oxidation numbers, for example.

WikiPremed Resources

Periodic Table
PDF of the periodic table

Periodic Properties Concepts
Concept chapter for Periodic Properties in PDF format

Periodic Properties Practice Items
Problem set for Periodic Properties in PDF format

Answer Key
Answers and explanations

Periodic Table with Electron Shells
PDF showing the relationship between the periodic table and electron configuration

Periodic Properties Images
Image gallery for study with links to larger teaching JPEGs for classroom presentation

Question Drill for Periodic Properties
Conceptual Vocabulary Self-Test

Basic Terms Crossword Puzzle

Basic Puzzle Solution

Learning Goals


Understand the rationale behind the organization of the periodic table and how the organization of the table relates to electronic structure.

Be able to define atomic radius and predict the relative sizes of atoms from their position on the periodic table.

Model the events described by electron affinity as well as ionization energy in your imagination. Understand the patterns of change in the energy involved for these events moving from left-to-right and up-and-down across the periodic table.

Clearly comprehend the context and meaning of electronegativity and how it changes across the periodic table.

Have a good handle on the respective chemical characteristics of alkali metals, alkaline earth metals, transition metals, the oxygen group, halogens, and noble gases.

Be sure to have memorized the values of the electronegativities of the important elements of organic chemistry including carbon, hydrogen, oxygen, nitrogen, and the halogens (and some of the alkali metals and sulfur and phosphorus too).

Suggested Assignments

Review the fundamental terminology for periodic properties using the question server. Complete the fundamental terms crossword puzzle. Here is the solution to the puzzle.

Study the periodic properties chapter. Perform the practice items. Here is the answer key for the problem set.

Take a review tour of the periodic properties web resources.

Conceptual Vocabulary for Periodic Properties

Periodic table
The periodic table of the chemical elements is a tabular method of displaying the chemical elements credited to Russian chemist Dmitri Mendeleev in 1869.
Chemical element
A chemical element is a type of atom that is defined by its atomic number; that is, by the number of protons in its nucleus.
Atomic number
The atomic number or proton number is the number of protons found in the nucleus of an atom.
A group, also known as a family, is a vertical column in the periodic table of the chemical elements.
Electronegativity is a chemical property which describes the power of an atom to attract electrons towards itself.
Ionization energy
The ionization energy of an atom or molecule is the energy required to remove one mole of electrons from one mole of isolated gaseous atoms or ions.
Chemical symbol
A chemical symbol is an abbreviation or short representation of the name of a chemical element, generally assigned in relation to its Latin name.
Noble gas
The noble gases are the elements in group 18 of the periodic table. It is also called helium family or neon family.
Transition metal
The term transition metal commonly refers to any element in the d-block of the periodic table, including zinc, cadmium and mercury. This corresponds to groups 3 to 12 on the periodic table.
Electron affinity
The electron affinity of an atom or molecule is the energy required to detach an electron from a singly charged negative ion or, inversely, the energy released when an electron is attached to a neutral atom or molecule.
Dmitri Mendeleev
Dimitri Mendeleev (1834 - 1907) was a Russian chemist credited as being the primary creator of the first version of the periodic table of elements.
Atomic mass
The atomic mass is the mass of an atom at rest.
Alkali metal
The alkali metals are a series of elements comprising Group 1 of the periodic table: lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr).
Alkaline earth metal
The alkaline earth metals are a series of elements comprising Group 2 of the periodic table: beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba) and radium (Ra).
The halogens are a series of nonmetal elements from Group 17 of the periodic table, comprising fluorine, F; chlorine, Cl; bromine, Br; iodine, I; and astatine, At.
Mass number
The mass number is the number of nucleons in an atomic nucleus.
Atomic mass unit
The unified atomic mass unit (u), or dalton (Da), is defined to be one twelfth of the mass of an unbound atom of the carbon-12 nuclide, at rest and in its ground state.
The s-block of the periodic table of elements consists of the first two groups: the alkali metals and alkaline earth metals, plus hydrogen and helium.
The p-block of the periodic table of the elements consists of the last six groups minus helium.
Atomic radius
The somewhat hazily defined physical property known as atomic radius represents a reasonable attempt to quantify the size of atoms and ions, based both on experimental measurements and calculational methods.
Advanced terms that may appear in context in MCAT passages
The d-block of the periodic table of the elements consists of those periodic table groups that contain elements in which, in the atomic ground state, the highest-energy electron is in a d-orbital.
The lanthanide series comprises the 15 elements with atomic numbers 57 through 71, from lanthanum to lutetium.
The actinide series encompasses the 15 chemical elements that lie between actinium and lawrencium on the periodic table, with atomic numbers 89 - 103.
Rare earth element
Rare earth elements and metals are a collection of sixteen chemical elements in the periodic table, namely scandium, yttrium, and fourteen of the fifteen lanthanoids (excluding promethium), which naturally occur on the Earth.
The f-block of the periodic table of the elements consists of those elements (sometimes referred to as the inner transition elements) for which, in the atomic ground state, the highest-energy electrons occupy f-orbitals.
The chalcogens are the name for the periodic table group 16 in the periodic table. It is sometimes known as the oxygen family.