Periodic Table, Electronic Configurations, and Ionic Bonding

Vocabulary practice flashcards generated from lecture material covering atomic structure, electronic configurations, ion formation, periodic table trends, and ionic compound ratios.

Atomic Number

The number of protons in an atom, which equals the number of electrons in a neutral atom.

Mass Number

The total number of protons and neutrons in an atom, where neutrons equal the mass number minus the atomic number.

Electron Shell Capacity

The maximum capacity of electrons per shell: up to 2 electrons in the 1st shell, up to 8 electrons in the 2nd shell, and up to 8 electrons in the 3rd shell.

Transfer

The movement of electrons from a metal atom to a non-metal atom.

Electrostatic Force

The attraction between opposite electrical charges.

Cation

A positively charged ion formed when an atom loses electrons.

Anion

A negatively charged ion formed when an atom gains electrons.

Valence Shell

The outermost electron shell of an atom.

Ionic Bond

A strong attraction between oppositely charged ions.

Noble Gas Configuration

A stable electron arrangement characterized by a full outer electron shell.

Magnesium Ion Formation

A magnesium atom with electronic structure $2,8,2$ loses 2 outer electrons to form a stable $Mg^{2+}$ ion.

Chloride Ion Formation

A chlorine atom with electronic structure $2,8,7$ gains 1 electron to form a stable $Cl^-$ ion.

Group 1 Ion Charge Trend

Atoms in Group 1 usually form ions with a charge of $1+$ by losing 1 outer-shell electron.

Group 2 Ion Charge Trend

Atoms in Group 2 usually form ions with a charge of $2+$ by losing 2 outer-shell electrons.

Group 16 Ion Charge Trend

Atoms in Group 16 usually form ions with a charge of $2-$ by gaining 2 electrons.

Sodium Oxide ($Na_2O$) Formation

An ionic compound where two Group 1 sodium atoms each lose 1 valence electron to supply the 2 electrons needed by one Group 16 oxygen atom to achieve a full octet.

Magnesium Chloride ($MgCl_2$) Ratio

An ionic compound formed in a ratio of $1:2$ of $Mg^{2+}$ to $Cl^-$ ions, because one magnesium atom loses 2 electrons and two chlorine atoms each gain 1 electron.

Periodic Table Group Number

Indicates the number of valence (outer-shell) electrons in an atom, which helps predict whether it loses or gains electrons to form an ion.

Periodic Table Period

Corresponds to the total number of occupied electron shells in an atom (for example, element $2,8,8,1$ occupies 4 shells and belongs to Period 4).