Mrs Roberts: Well, the modern periodic table shows us all of the elements arranged in rows, which are called periods. It has changed a lot over the years as we've learned more and more about atoms.

The periodic table of chemical elements, often called the periodic table, organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic ...

In 1843, Leopold Gmelin worked with the Dobereiner’s system and developed a table of 55 elements that contained many of the similar relationships later found in the modern periodic table. Then in 1857 ...

118 Elements and Their Symbols and Atomic Numbers ... The periodic table that we follow for our studies is the Modern Periodic Table, which is based on atomic number rather than atomic mass.

But how many of these elements do you know? Test your knowledge and compete with other Live Science readers to see who can ...

The Periodic Table is an amazing chemistry tool that is organized with elements in order of increasing atomic number. The properties of the element change as you move across the row, but are similar ...

With Glenn T. Seaborg's 1945 discovery that the actinides were in fact f-block rather than d-block elements, a recognisably modern form of the table was reached. The periodic table and law are now a ...