Because the properties of the elements change in a periodic fashion. In the early versions, when fewer elements were known, the chemically similar elements were thought to occur every eight positions.
Mendeleev predicted that properties of elements are periodic function of atomic mass. He demonstrated it by creating a table.
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Mendeleev's periodic table arranged elements by increasing atomic mass and grouped elements with similar properties together. Today's periodic table is similar, but it is arranged by increasing atomic number, which reflects the number of protons in an atom's nucleus. Both tables also show periodic trends in properties as you move across and down the table.
It is named The PERIODIC TABLE. The periods being the horizontal rows The groups being the vertical columns.
The rows in the periodic table are called periods. There are 7 periods in periodic table.
To understand the concept of Periodic Table
In Mendeleev's periodic table, the elements were arranged in the increasing order of their atomic masses and repeating periodic properties.
Mendeleev predicted that properties of elements are periodic function of atomic mass. He demonstrated it by creating a table.
they changed the 3 new Elements.
elements
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Dmitri Mendeleev was a Russian chemist; he proposed the modern Periodic Table of elements in 1869.
Mendeleev's periodic table arranged elements by increasing atomic mass and grouped elements with similar properties together. Today's periodic table is similar, but it is arranged by increasing atomic number, which reflects the number of protons in an atom's nucleus. Both tables also show periodic trends in properties as you move across and down the table.
It is called the Periodic Table of Elements.
It is named The PERIODIC TABLE. The periods being the horizontal rows The groups being the vertical columns.
Actually, Dmitri Mendeleev formulated the periodic law and published his periodic table of elements in 1869. This table arranged elements by increasing atomic mass and grouped them based on similar properties, predicting the properties of missing elements. It was a significant contribution to the field of chemistry.
Periodic table comprises of rows and columns like in an organised manner. Hence, it is called a table.