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प्रश्न
Why was Dobereiner's triad discarded?
उत्तर
Döbereiner failed to arrange all the known elements in the form of triads.
In the triad of fluorine (19), chlorine (35.5) and bromine (80), it is observed that the mean of the atomic masses of fluorine and bromine is ½(19 + 80) = 49.5, not 35.5.
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संबंधित प्रश्न
Did Dobereiner’s triads also exist in the columns of Newlands’ Octaves? Compare and find out.
A, B and C are the elements of a Dobereiner's triad. If the atomic mass of A is 7 and the of C is 39, what should be the atomic mass of B?
State one example of a Dobereiner's triad, showing in it that the atomic mass of middle element is half-way between those of the other two.
Can the following groups of elements be classified as Dobereiner's triads?
(a) Na, Si, Cl
(b) Be, Mg, Ca
Give reason for your answer.
(Atomic masses : Be 9 ; Na 23 ; Mg 24 ; Si 28 ; Cl 35.5 ; Ca 40)
With an example, explain Dobereiner's Triads.
Can the following groups of elements be classified as Dobereiner's triad:
Na, Si, Cl
Atomic mass of Na - 23, Si - 28, Cl - 35.
Justify your answer.
Can the following groups of elements be classified as Dobereiner's triad:
Be, Mg, Ca
Atomic mass of Be - 9, Mg - 24, Ca - 40.
Justify your answer.
Find the odd one out and give its explanation.
If Dobereiner is related with ‘law of triads’, then Newlands is related with ______.
Pick out the chemically most reactive elements from the given triads.
Li, Na, K F, Cl, Br
