Review of the Periodic Table

Flashcards about the periodic table, its history, families, and properties of elements, along with Lewis Diagrams.

When were there only 4 known elements?

330 BC

When were there 31 known elements?

1800

When were there 63 known elements?

1865

Why was the development of the periodic table important?

Chemists needed a systematic way to organize the elements.

When did Johann Dobereiner propose the Law of Triads?

1829

According to Dobereiner's Law of Triads, which elements had similar atomic masses?

Lithium, potassium, and sodium.

What are triads according to Dobereiner?

Groups of three elements with similar properties.

In what year did John Alexander Newlands arrange all known elements by atomic mass?

1864

What observation did Newlands make when arranging elements by atomic mass?

Every eighth element had similar physical and chemical properties (Law of Octaves).

What did Newlands do with elements having similar properties?

He grouped the elements into families.

In what year did Dimitri Mendeleev organize elements by atomic masses?

1869

Who is credited as the Father of the Periodic Table?

Dimitri Mendeleev

How did Mendeleev organize the elements?

Elements were arranged 'periodically' with elements of similar properties under each other.

In what year did Henry Moseley determine the atomic number of each element?

1913

What did Henry Moseley contribute to the periodic table?

He determined the atomic number of each of the elements and modified the Periodic Law.

How does the modern periodic table organize elements?

Elements are organized based on their atomic number.

What is the modern definition of the Periodic Law?

The chemical and physical properties of the elements repeat in a regular, periodic pattern when they are arranged according to their atomic number.

Name some of the families of the periodic table.

Alkali Metals, Alkali Earth Metals, Transition Metals, Actinide Series, Lanthanide Series, Boron Family, Carbon Family, Nitrogen Family, Oxygen Family, Halogen Family, Noble Gases.

Where are metals located on the periodic table?

Left and center of the periodic table.

What are some properties of metals?

Conduct heat and electricity, ductile and malleable, shiny, often silvery-grey, solid at room temperature (except mercury).

How does Hydrogen behave?

It sometimes behaves like an alkali metal, sometimes like a halogen, and sometimes in its own unique way.

Where are non-metals located on the periodic table?

Right side of the periodic table.

What are the properties of non-metals?

Poor conductors of heat and electricity, usually solid or gas at room temperature (except bromine), brittle, dull.

What do Metalloids do?

They separate metals from non-metals.

What are properties of metalloids?

Properties intermediate between metals and non-metals (e.g., silicon, tellurium).

What do all atoms of elements in the same group have in common?

Same number of valence electrons.

How does the group number relate to the number of valence electrons?

As the group number increases, so does the number of valence electrons.

What do all atoms of elements in the same period have in common?

Same number of shells (orbits).

How does the period number relate to the number of shells?

As the period number increases, so does the number of shells.

What is a Lewis dot diagram?

A drawing of an atom with ONLY its valence electrons.