Periodic Table: Key Concepts and Element Properties

Who compiled a list of known elements in the 1700s?

Antoine Lavoisier

What arrangement did John Newlands propose for elements?

Ordered by increasing atomic mass

What pattern did Newlands notice in the properties of elements?

Properties repeated every eighth element

Which two chemists demonstrated a connection between atomic mass and elemental properties?

Lothar Meyer and Dimitri Mendeleev

What did Henry Moseley rearrange the periodic table by?

Increasing atomic number

What is the periodic law?

Periodic repetition of chemical and physical properties when arranged by increasing atomic number

What information is contained in the boxes of the modern periodic table?

Element's name, symbol, atomic number, and atomic mass

What are the columns of elements in the periodic table called?

Groups

What are the rows of elements in the periodic table called?

Periods

What are the representative elements?

Elements in groups 1, 2, and 13-18 with a variety of properties

What are the transition metals?

Elements in groups 3-12

What are alkali metals?

Elements in group 1 (except hydrogen) that are very reactive

What are alkaline earth metals?

Elements in group 2 that are highly reactive

What are the two sets of inner transition metals called?

Lanthanide series and actinide series

What are nonmetals generally like?

Gases or brittle, dull-looking solids that are poor conductors

What are halogens?

Highly reactive elements in group 17

What are noble gases?

Extremely unreactive gases in group 18

What are valence electrons?

Electrons in the highest principal energy level

What does the s block of the periodic table include?

Groups 1 & 2 (including helium) and holds 2 electrons

What does the p block of the periodic table include?

Groups 13-18 and holds 6 electrons

What is the atomic radius?

Half the distance between adjacent nuclei in a crystal of the element

What happens to the atomic radius when atoms lose electrons?

They become smaller due to loss of a valence electron and decreased electrostatic repulsion

What is ionization energy?

The energy required to remove an electron from a gaseous atom

What is the octet rule?

Atoms tend to gain, lose, or share electrons to acquire a full set of eight valence electrons

What does electronegativity indicate?

An element's relative ability to attract electrons in a chemical bond

How does electronegativity change across a period?

It increases left to right and decreases down a group