Chapter 4
the law that states that the properties of the elements vary with their atomic numbers in a regular, repeated pattern
What is periodic law.
an element with characteristics between those of metals and nonmetals; also called semi-conductors
metalloid
an element in Group 17 of the periodic table having seven valence electrons
halogen
a column of elements in the periodic table having similar valence electron arrangement, resulting in similar chemical properties; also known as a group
family
an element in Group 1 of the periodic table, having one valence electron that it can easily lose to form a 1+ cation, making it extremely reactive
alkali metals
How many people live in lancaster?
What is 59000.
an electron in the outermost energy level of a neutral atom
valence electron
an element in Group 2 of the periodic table, having two valence electrons that it tends to lose easily to become a 2+ cation, making it very reactive
alkaline-earth metals
How many people live in United States?
What is 328.2 million
a row in the periodic table of the elements; also called a series
period
any elements in Groups 3–12 of the periodic table, typically having one or two valence electrons, which are easily lost, resulting in cations with charges of 1+ or 2+
transition metals
How many people live in PA?
What is 12.8 million.
an element that is typically dense, solid, ductile, malleable, highly conductive, and chemically reactive, especially in the presence of nonmetal elements
metal
any of groups 13-16 in the periodic table; so named because they contain metals, nonmetals, and metalloids
mixed groups
How many people live in the world?
What is 7.5 Billion