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प्रश्न
According to Dobereiner’s triads rule, three elements in an increasing order of atomic mass shows _______.
उत्तर
According to Dobereiner’s triads rule, three elements in an increasing order of atomic mass shows the atomic mass of the middle element in each triad approximately equal to the mean of the atomic masses of the other two elements.
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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.
The atomic masses of three elements X, Y and Z having similar chemical properties are 7, 23 and 39 respectively.
(a) Calculate the average atomic mass of elements X and Z.
(b) How does the average atomic mass of elements X and Z compare with the atomic mass of element Y?
(c) Which law of classification of elements is illustrated by this example?
(d) What could the elements X, Y and Z be?
(e) Give another example of a set of elements which can be classified according to this law.
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)
In Dobereiner’s triads Li, Na, K, the atomic masses of Lithium and Potassium are 6.9 and 39.1 respectively, then what will be the atomic mass of sodium?
Why was Dobereiner's triad discarded?
Did Dobereiners triads also exist in the columns of Newland's Octaves? Compare and find out.
With an example, explain Dobereiner's Triads.
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.
What was Dobereiner’s basis, of classification of elements?
Explain why Dobereiner’s method of classification of elements did not hold much weightage for future classification.
Dobereiner laid down the _______ rule.
Find the odd one out and give its explanation.
Find the odd one out and give its explanation.
Write the characteristic of Dobereiner’s triads?
Write the name.
The atom having the biggest atomic size from period 2.
In Dobreiner's triads, three elements appear to be arranged in ascending order of their atomic number.
State Dobereiner’s Law of Triads.
If Dobereiner is related with ‘law of triads’, then Newlands is related with ______.
Match the following.
| 1. | Triads | Newlands |
| 2. | Alkali metal | Calcium |
| 3. | Law of octaves | Henry Moseley |
| 4. | Alkaline earth metal | Sodium |
| 5. | Modern Periodic Law | Dobereiner |
Pick out the chemically most reactive elements from the given triads.
Li, Na, K F, Cl, Br
