Historical Devt of Periodic Table

He observed that the order of the X-ray frequencies emitted by elements follows the ordering of the elements by atomic number.

• John Newlands

• Johann Dobereiner

• Henry Moseley

• Dmitri Mendeleev

A German chemist who formed the triads of elements with similar properties.

• John Newlands

• Johann Dobereiner

• Henry Moseley

• Dmitri Mendeleev

A Russian chemist who arranged the elements in order of increasing atomic mass while putting in groups those with similar properties and even left blank spaces in his table.

• John Newlands

• Johann Dobereiner

• Henry Moseley

• Dmitri Mendeleev

An English chemist who proposed the Law of Octaves based on the similar properties for every eight elements when arranged in increasing atomic mass.

• John Newlands

• Johann Dobereiner

• Henry Moseley

• Dmitri Mendeleev

How are the vertical columns of the periodic table called?

• Families

• Groups

• Periods

• Rows