Chemical experiments on the element proved that Mendeleev's suggestions were correct; along with discovery and characterization of gallium and germanium this proved the correctness of the whole periodic table and periodic law.
12.
Meyer, as well as other chemists, was doubtful about Mendeleev's periodic law, and he criticized Mendeleev for " changing existing elements'atomic weights, only regarding possibility of periodical law in its structure ".
13.
Date of readings is due to two dates : birthday of Dmitri Mendeleev ( 8 February 1834 ), and sending messages to them on the opening Periodic Law ( March 1869 ).
14.
:: : : Done " Its position in the periodic table is between rhenium and manganese and as predicted by periodic law its properties are intermediate between those two elements . "-- mav
15.
Mendeleev questioned some of the currently accepted atomic weights ( they could be measured only with a relatively low accuracy at that time ), pointing out that they did not correspond to those suggested by his Periodic Law.
16.
The Royal Chemistry Society acknowledged Newlands'contribution to science in 2008, when they put a Blue Plaque on the house where he was born, which described him as the " discoverer of the Periodic Law for the chemical elements ".
17.
It is this periodicity of properties, manifestations of which underlying theory was developed, that led to the establishment of the periodic law ( the properties of the elements recur at varying intervals ) and the formulation of the first periodic tables.
18.
;1860 : Stanislao Cannizzaro, resurrecting Avogadro's ideas regarding diatomic molecules, compiles a table of atomic weights and presents it at the 1860 Karlsruhe Congress, ending decades of conflicting atomic weights and molecular formulas, and leading to Mendeleev's discovery of the periodic law.
19.
J . A . R . Newlands ( 1837 1898 ), the Victorian chemist who discovered the Periodic Law for the chemical elements, was born and raised in No . 19 . A blue plaque, installed by the Royal Society of Chemistry, commemorates Newlands on the front of the house.
20.
Mendeleev had such faith in the validity of the periodic law that he proposed changes to the generally accepted values for the atomic weight of a few elements and, in his version of the periodic table of 1871, predicted the locations within the table of unknown elements together with their properties.
