Periodic Table, Atomic Structure, Isotopes, and Ions Vocabulary

A complete set of vocabulary flashcards covering periodic table organization, isotopic notation, isotopes of hydrogen, ions, and atomic calculations.

Periodic Table

An arrangement of the elements based on repeating properties.

Period

A horizontal row of elements on the periodic table across which properties vary; there are 7 periods on the periodic table.

Group

A vertical column of elements on the periodic table whose elements share similar chemical and physical properties; there are 18 groups on the periodic table.

Atomic Number

The number of protons in the nucleus of an atom, which distinguishes elements from one another and is always a whole number on the periodic table.

Mass Number

The total number of protons plus neutrons in an atom, which is usually a decimal on the periodic table because it represents an average atomic mass.

Element Symbol

A chemical abbreviation that tells which element an atom is.

Isotopic Symbol Mass Number Position

The upper left position in an isotopic symbol.

Isotopic Symbol Atomic Number Position

The lower left position in an isotopic symbol.

$$^{35}_{17}\text{Cl}$$

Isotopic symbol representing Chlorine-35 with 17 protons and 18 neutrons.

$$^{11}_{5}\text{B}$$

Isotopic symbol representing Boron-11 with 5 protons and 6 neutrons.

$$^{11}_{5}\text{B}^{3-}$$

Isotopic symbol representing Boron-11 with 5 protons, 6 neutrons, and a $3-$ charge.

Isotope

Atoms of the same element with the same number of protons but different numbers of neutrons and mass numbers, which are chemically alike.

H-1

A form of hydrogen with 1 proton and 0 neutrons.

Deuterium (H-2)

A form of hydrogen with 1 proton and 1 neutron.

Tritium (H-3)

A form of hydrogen with 1 proton and 2 neutrons.

Ion

An atom with a charge.

Neutral Atom

An atom that has equal numbers of protons and electrons, resulting in no net charge.

Cation

A positive ion that has more protons than electrons, formed when an atom loses electrons.

Anion

A negative ion that has more electrons than protons, formed when an atom gains electrons.

Calculation of Neutrons

Determined using the formula: $\text{Neutrons} = \text{mass number} - \text{atomic number}$.

Calculation of Charge

Determined using the formula: $\text{Charge} = \text{protons} - \text{electrons}$.

Calculation of Protons

Determined by: $\text{Protons} = \text{atomic number}$.

Calculation of Electrons in a Neutral Atom

Determined by: $\text{Electrons} = \text{atomic number}$.