Question

In Dobereiner's triad containing Li, Na, K, if atomic masses of Lithium & Potassium are 6.9 and 39.1, then what will be the atomic mass of Sodium ?

Answer 1

According to dobereiner, average of atomic masses of 1st and 3rd atom.

Atomic mass of Na=6.9+39.1 /2

=46/2 = 23u

Hope it helps*_*

Answer 2

Then the atomic mass of sodium will be 23
Na =( 7+ 39 )/2 =23