In the periodic table of elements, how are periods organized?
A)Vertically, into columns
B)Horizontally, into rows
C)By their abundance
D)Alphabetically

Question

Quizplus · Accepted Answer

In the periodic table of elements, periods are organized horizontally, into rows. Elements in the same period, or row, have the same number of atomic orbitals or electron shells. The number of orbitals or electron shells increases from top row to bottom row.

In the Periodic Table of Elements, How Are Periods Organized