Besides gallium, which other elements have since been discovered that were left by Mendeleev in his Periodic Table? (Any two)
Germanium(Ge) and Scandium(Sc) are the elements that are left by Mendeleev in his Periodic Table since its discovery.
Periodic Classification of Elements
Use Mendeleev’s Periodic Table to predict the formulae for the oxides of the following elements: K, C, AI, Si, Ba.
K- K2O C- C2O4 or CO2 Al- Al2O3 Si- Si2O4 or SiO2 B – Ba2O2 or BaO Group VI A of Mendeleev\’s periodic table is where oxygen belongs. The value of it is 2. All of the elements listed can also have their valencies inferred from the groups to which they belong. This will make …
What were the limitations of Newlands’ Law of Octaves?
Limitations of Newlands’ Law of Octaves are as follows: (i) Only elements up to calcium are applicable to Newlands\’ Law of Octaves.(ii) Newland assumed that there were 56 elements in nature and that no new elements could be found.(iii) Newland combined two elements into one slot in order to fit them into the table. Newland …
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What were the limitations of Döbereiner’s classification?
(I) They did not apply to elements with very low or very high masses. (ii) Dobereiner\’s triads couldn\’t fit all of the elements. (iii) As the methods to calculate atomic mass improved, Dobereiner’s triads’ validity began to decrease. For example, in the triad of F, Cl and Br, the arithmetic mean of atomic masses of …
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Did Döbereiner’s triads also exist in the columns of Newlands’ Octaves? Compare and find out.
The columns of Newlands\’ Octaves actually contains Döbereiner\’s triads; for example, the elements A Dobereiner\’s Triad is made up of the elements lithium (Li), potassium (K), and sodium (Na), although they can also be found in the second column of Newland\’s Octaves.