Periodic Table Notes (L2 - Full)

John Newlands; it was one of the earliest systematic arrangements and predicted unknown elements

Dmitri Mendeleev; it was the first periodic table based on atomic mass

Henry Moseley; it introduced the concept of atomic number

Marie Curie; it led to the discovery of radioactivity

It organizes elements by increasing atomic number.

Elements are grouped by shared physical and chemical properties.

The periodic table was first organized by atomic mass.

Every element's square contains its chemical symbol.

Atomic number, chemical symbol, atomic mass, element name

Atomic number, melting point, atomic mass, element name

Chemical symbol, boiling point, atomic mass, element name

Atomic number, chemical symbol, density, element name

A horizontal row; atomic number increases by 1 from left to right

A vertical column; atomic number stays the same

A diagonal line; atomic number decreases

A group of elements with similar properties; atomic number is random

Groups are vertical columns on the periodic table

Elements in the same group have the same number of valence electrons

There are 18 groups in the periodic table

Groups are horizontal rows on the periodic table

Hard and shiny

Good conductors of heat and electricity

Highly reactive with water

Often used in building materials and electronics

Carbon Group

Boron Group

Oxygen Group

Halogen Group

Carbon (C)

Silicon (Si)

Germanium (Ge)

Gallium (Ga)

Atomic radius

Ionization energy

Electronegativity

Reactivity

Nuclear charge

Shielding effect

Atomic mass

Ionization energy

Atom size decreases across a period due to higher nuclear charge.

Atom size increases down a group due to higher shielding effect.

Atom size increases across a period due to higher shielding effect.

Atom size decreases down a group due to higher nuclear charge.

Electronegativity increases down a group.

Electronegativity decreases across a period.

Electronegativity increases across a period.

Electronegativity remains constant across a period.