PERIODIC TABLE FATHERS

JOHANN DOBREINER

• Atomic masses At this time, scientists had begun to find out the relative
• atomic masses of the elements. Dobereiner discovered that the

Antoine-Laurent Lavoisier

• was his systematic determination of the weights of reagents
• and products involved in chemical reactions, including
• gaseous components, and his underlying belief that matter
• identified by weight—would be conserved through any reaction

A.E.Beguyer de Chancourtois

• was the first person to make use of atomic
• weights to reveal that the elements were arranged according to their
• atomic weights with similar elements occurring at regular intervals

JOHN NEWLAND

• an English chemist, proposed the
• the Law of Octaves which stated that elements
• repeated their chemical properties every eighth element.

Dmitri Ivanovich Mendeleev

• Mendeleev predicted the existence and properties of unknown element
• which he called eka-aluminum, eka-boron, and eka-silicon

WILLIAM RAMSAY

• Sir William Ramsay was the Scottish scientist who discovered the noble gases.
• These gassesare argon,neon,krypton,and xenon

HENRY MOSELEY

• Using atomic number instead of atomic mass as the organizing principle
• was first proposed by the British chemist Henry Moseley in 1913
• and it solved anomalies like this one