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Chemistry · Classification of Elements and Periodicity in Properties
हिन्दीAccording to Dobereiner's triads, if the atomic weights of the first and third elements of a triad are \( 7 \) and \( 39 \) respectively, calculate the atomic weight of the middle element.
Correct answer · Option 2
23
Explanation
The atomic weight of the middle element in a Dobereiner's triad is the arithmetic mean of the atomic weights of the other two elements: \( \frac{7 + 39}{2} = 23 \).
