A, B and C are the elements of a Dobereiner’s triad. If the atomic mass of A is 7 and that of C is 39, what should be the atomic mass of B?
A, B and C are the elements of Dobereiner's triad.
Atomic mass of A = 7
Atomic mass of C = 39
According to Dobereiner's triad law, the atomic mass of B is the average of the atomic masses of A and C.
So, the average of the atomic masses of A and C
=( 7+39)/2
=46/2
=23
Therefore, the atomic mass of B is 23.
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