Chapter 5: The Periodic table and
Periodic Law
Section 1: Development of the Modern Periodic
Table
● Chemists use the periodic table to organize elements based on their similarities. In the
late 1700’s, French scientist Antoine Lavoisier compiled a list of all the known elements
that were known at the time.
● During the 1800, scientists developed techniques for separating different elements and
identifying their characteristics
● As new elements were discovered. Scientists learned a lot about their physical and
chemical properties they observed patterns of similar properties among groups of
elements
● John Newlands, meyer, Mendeleev, and moseley all studied and contributed to the
development of the periodic table
John Newlands
● Date: 1864
● ENglish chemist proposed a new way to organize the elements. He observed that when
the elements were arranged by increasing atoms, properties of each eighth element
were similar. The trend is said to be Periodic and it repeats in a specific manner.
● JN observed that the pattern resembled the repetition of musical notes in octaves
● During the 1860’s several chemists worked to apply observations of periodic trends to
patterns of properties of the elements
● Lothar Meyer and Dmitri Mendeleev worked independently of each other and
demonstrated a connection between atomic mass and the properties of elements that
showed a periodic pattern.
● Mendeleev is known as the father of the periodic table. He was the first of the two
chemists to publish his periodic table findings
● Mendeleev predicted the existence and properties of undiscovered elements that were
later identified. In his periodic table he left blank spaces where he thought the
undiscovered elements should go. He predicted the existence of scandium, gallium, and
germanium in a paper published in 1871.
● These three elements were discovered later and supported Mendeleev's published work
over the periodic table and its patterns. Galium in 1875. Scandium and Germanium in
1879
● Some elements were incorrectly group based on their atomic masses
● Mosley determined the reason for the misplacement of elements on Mendeleev's
periodic table.
Periodic Law
Section 1: Development of the Modern Periodic
Table
● Chemists use the periodic table to organize elements based on their similarities. In the
late 1700’s, French scientist Antoine Lavoisier compiled a list of all the known elements
that were known at the time.
● During the 1800, scientists developed techniques for separating different elements and
identifying their characteristics
● As new elements were discovered. Scientists learned a lot about their physical and
chemical properties they observed patterns of similar properties among groups of
elements
● John Newlands, meyer, Mendeleev, and moseley all studied and contributed to the
development of the periodic table
John Newlands
● Date: 1864
● ENglish chemist proposed a new way to organize the elements. He observed that when
the elements were arranged by increasing atoms, properties of each eighth element
were similar. The trend is said to be Periodic and it repeats in a specific manner.
● JN observed that the pattern resembled the repetition of musical notes in octaves
● During the 1860’s several chemists worked to apply observations of periodic trends to
patterns of properties of the elements
● Lothar Meyer and Dmitri Mendeleev worked independently of each other and
demonstrated a connection between atomic mass and the properties of elements that
showed a periodic pattern.
● Mendeleev is known as the father of the periodic table. He was the first of the two
chemists to publish his periodic table findings
● Mendeleev predicted the existence and properties of undiscovered elements that were
later identified. In his periodic table he left blank spaces where he thought the
undiscovered elements should go. He predicted the existence of scandium, gallium, and
germanium in a paper published in 1871.
● These three elements were discovered later and supported Mendeleev's published work
over the periodic table and its patterns. Galium in 1875. Scandium and Germanium in
1879
● Some elements were incorrectly group based on their atomic masses
● Mosley determined the reason for the misplacement of elements on Mendeleev's
periodic table.
