Question

in dobereiner's triad Li, Na, K if atomic mass of lithium and potassium are 6.9 and 39.1 , than what will be the mass of sodium

Answer 1

Hey there !

According to the features of a Döbereiner’s triad, the atomic mass of Na being the middle element must be roughly the average of the atomic masses of the other two elements which are Li and K. So, it’s mass is roughly (6.9+39.1)/2 = 46/2 = 23 u

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