History of the Periodic Table Notes
1. During the nineteenth century, how did the chemists began to categorize the elements on the periodic table? 2. What was the end result of this method? The chemists began to categorize the elements according to similarities in their physical and chemical properties. The end result of this method was our modern periodic table we use today
WHO: Johann Dobereiner Law of Triads 1780 - 1849 WHEN: WHAT: WHY: Example: Law of Triads 1829 Classified some elements into groups of three called triads. 1780 - 1849 Based the triads on similarities between chemical and physical properties of the elements
Law of Octaves WHO: John Newlands WHEN: WHAT: 1838 - 1898 WHY: Example: John Newlands 1863 Arranged the elements in order of increasing atomic mass Law of Octaves 1838 - 1898 Certain properties repeated every 8th element
WHO: Dmitri Mendeleev Modern Periodic Table 1834 - 1907 WHEN: 1869 WHAT: EXAMPLE: Dmitri Mendeleev 1869 Modern Periodic Table Organized periodic table by increasing atomic mass 1834 - 1907
Published own periodic table based on increasing atomic mass WHO: WHEN: WHAT: Published own periodic table based on increasing atomic mass Lothar Meyer 1869 ( a couple months after Mendeleev) 1830 - 1895 Published his own table of elements organized by increasing atomic mass
Elements known at this time Both Mendeleev and Meyer arranged the elements in order of increasing atomic mass. Both left vacant spaces where unknown elements should fit.
Mendeleev wins the title because... He corrected the atomic masses of Be, In, and U He used his periodic table to predict the physical properties of three elements that were yet unknown.
Increasing atomic number WHO: WHEN: WHAT: Henry Moseley Increasing atomic number 1913 Determined the nuclear charge (atomic number) of the elements 1887 - 1915 Rearranged the elements in order of increasing atomic number
Periodic Law When elements are arranged in order of increasing atomic number, there is a periodic pattern in their physical and chemical properties.
The horizontal rows of the periodic table are called PERIODS.
The vertical columns are called GROUPS, or FAMILIES. The elements in the same group have similar physical and chemical properties!
Periodic Table Geography Fill out the following on your Periodic Table!
Metals vs. Nonmetals Outline the metals red.
metals
Metals vs. Nonmetals Outline the metals red. Outline the nonmetals blue.
metals nonmetals
Metals vs. Nonmetals Metalloids Outline the metals red. Outline the nonmetals blue. Outline the metalloids green Metalloids
metals nonmetals metalloids
Metals and nonmetals can be split into 5 subgroups Alkai Metals Alkaline Earth Metals Transition Metals Halogens Nobel Gases
Group 1: Alkali Metals
Group 2: Alkaline Earth Metals
Groups 3-12: Transition Metals
Group 17 (7A): Halogens
Group 18 (8A): Noble Gases
Valence Electrons