On the periodic table, the seven horizontal rows are called periods. On the left-hand side of the periodic table, the row numbers are given as one through seven. Moving across a period from left to right, the atomic number of the elements increases.Know More
Rows six and seven contain elements called transition elements, which are subdivided into the actinide and lanthanide series. While the elements numbered 58 through 71 are the lanthanide series, elements with the numbers 90 through 103 are the actinide series.
The vertical columns on this table are called groups. Groups are sometimes called families because the elements in them share certain physical and chemical properties. In the older system, these groups were given the Roman numerals I through VIII. In the new system, they are designated as groups 1 through 18.Learn more about Atoms & Molecules
Mendeleev arranged the periodic table in order of increasing atomic weight of the elements. He determined that there was a pattern when he arranged these elements into horizontal rows.Full Answer >
Elements become denser toward the bottom of the periodic table. From left to right on the table, elements become denser toward the center of the table and less dense on either end.Full Answer >
The MCAT periodic table is the periodic table made available to test takers of the Medical College Admission Test (MCAT). It includes the same information as typical periodic tables, listing the atomic numbers and atomic weights of each element.Full Answer >
The symbol "Cd" stands for the element cadmium on the periodic table. The atomic number of cadmium is 48, and its atomic weight is 112.404 atomic mass units. Cadmium is a heavy metal that belongs to the fifth period on the periodic table.Full Answer >