Dobreiner Triads
Dobreiner Triads
Dobereiner’s Triads (1817):
In the year 1817, Johann Wolfgang Döbereiner, a German chemist; has made an attempt to arrange the elements with similar properties into groups having three elements each. He called these groups as triads. Döbereiner showed that when the three elements in a triad were arranged in the order of increasing atomic masses, the atomic mass of the middle element was roughly the average of the atomic masses of the two elements.
Importance:
The given classification of elements into triads had a great significance in predicting atomic mass and properties of middle element. Even in these days, these elements resemble in their properties.
Limitation:
All the elements discovered at that time could not be classified into triads. Döbereiner could identify only three triads from the elements known at that time. These are: Li, Na, K Ca, Sr Ba Cl, Br, I
Which of the following was the triad given by Döbereiner ? | |||
| Right Option : D | |||
| View Explanation | |||
Döbereiner showed that when the three elements in a triad were arranged in the order of increasing ________________________. | |||
| Right Option : A | |||
| View Explanation | |||
Döbereiner showed that when the three elements in a triad were arranged in the order of _____________________________. | |||
| Right Option : A | |||
| View Explanation |
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