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प्रश्न
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?
उत्तर
According to Doberiner’s triads, the average atomic mass of two elements is the atomic mass of the third element in a series Na and K.
Average atomic mass of sodium = `"Atomic mass of Li and K"/2`
`= (6.9+39.1)/2`
= `46/2`
= 23
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