Atomic Radius
defined as a predictable way that elements tend to change as one moves along a group or period
What is a trend?
rows on the periodic table (horizontal)
What are periods?
Lanthanides and Actinides
What are inner transition metals?
Electrons in the highest energy level (outermost level)
What are valence electrons?
an atom or bonded group of atoms that has a positive or negative charge
What is an ion?
Generally there is a ___________in atomic radii as one moves from left to right across a period.
What is decrease?
vertical columns on the periodic table
What are groups?
numbers 58 to 71 and 90 to 103
What are inner transition metals?
or
What are lanthanides and actinides?
groups 1 and 2, and the element helium
What is the s-block of the periodic table.
elements that are generally gases or brittle, dull-looking solids
What are nonmetals?
Atomic radii _______________ as one moves down a group.
What is increase?
The most important characteristic of akali metals
What is highly reactive?
The representative elements
What are groups 1,2, 13-18?
This block contains inner transition metals.
What is the f-block?
elements that are generally shiny when smooth and clean and that are good conductors of heat and electricity
What are metals?
Atomic size is influenced by this.
What is electron configuration?
Group 17 elements that are part of compounds and highly reactive
What are halogens?
Groups 3 - 12
What are transition metals?
Groups 13 to 18 of the periodic table are called this.
What is the p-block?
There is a repetition of chemical and physical properties of elements when they are arranged by increasing atomic number.
What is periodic law?
How this measurement is calculated depends on whether the atom is part of a molecule, is metal, or nonmetal.
What is atomic radius?
Group 18 elements that are very nonreactive
What are noble gases?
Group 2 elements that are highly reactive
What are alkaline earth metals?
The largest block, and it contains the transition metals.
What is the d block?
He discovered that each element has a unique number of protons.
Who is Henry Moseley?