julius lothar meyer developed the first periodic table with 8 columns.
julius lothar meyer developed the first periodic table with 8 columns.
who developed the first periodic table with 8 columns?
julius lothar meyer
an important breakthrough in making sense of the list of known chemical elements (as well as in understanding the internal structure of atoms) was dmitri mendeleev's development of the first modern periodic table, or the periodic classification of the elements. mendeleev, a russian chemist, felt that there was some type of order to the elements and he spent more than thirteen years of his life collecting data and assembling the concept, initially with the idea of resolving some of the disorder in the field for his students. mendeleev found that, when all the known chemical elements were arranged in order of increasing atomic weight, the resulting table displayed a recurring pattern, or periodicity, of properties within groups of elements. mendeleev's law allowed him to build up a systematic periodic table of all the 66 elements then known based on atomic mass, which he published in "principles of chemistry" in 1869. his first periodic table was compiled on the basis of arranging the elements in ascending order of atomic weight and grouping them by similarity of properties.
history of chemistry
german chemist lothar meyer also noted the sequences of similar chemical and physical properties repeated at periodic intervals. according to him, if the atomic weights were plotted as ordinates and the atomic volumes as abscissas—the curve obtained a series of maximums and minimums—the most electropositive elements appearing at the peaks of the curve in the order of their atomic weights. in 1864, a book of his was published; it contained an early version of the periodic table containing 28 elements, classified elements into six families by their valence—for the first time, elements had been grouped according to their valence. works on organizing the elements by atomic weight until then had been stymied by inaccurate measurements of the atomic weights. in 1868, he revised his table, but this draft table was published only after his death. in a paper dated december 1869 which appeared early in 1870, meyer published a new periodic table of 55 elements, in which the series of periods are properly ended by an element of the alkaline earth metal group. the paper also included a line chart of relative atomic volumes, which illustrated periodic relationships of physical characteristics of the elements, and which assisted meyer in deciding where elements should appear in his periodic table. by this time he had already seen the publication of mendeleev's first periodic table, but his work appears to have been largely independent.
history of the periodic table