4.2 Flashcards
1
Q
Actinides
A
A special block of metallic elements with atomic numbers 90-103
2
Q
Groups
A
Vertical columns of the periodic table;group number is equal to the number of electrons in the outer shell of atoms of the elements in that group
3
Q
Lanthanides
A
A special block of metallic elements with atomic numbers 58-71
4
Q
Period table
A
A list of all the known elements arranged horizontally in order of increasing atomic number and vertically according to the number of electrons in the outer shell
5
Q
Periods
A
Horizontal rows of the periodic table; period number of an element is equal to the number of electrons in the outer shells
6
Q
Transition elements
A
A special block of metallic elements cover elements from group 3-12
