Question

light
2) (A,B,C) is a Dobereiner's triad. Complete the following chart and
give reason for the answer.
Elements
А
B
С
Atomic mass
6.9
23
c=?​

Answer 1

According to Dobreiner's triad, the atomic mass of the central element (B) is the arithmetic mean of the atomic masses of the other two elements (A and C ).

Given that: A=7, B=15

Let the mass of C be M

C

.

M

B

=

2

M

A

+M

C

15=

2

7+M

c

⇒M

C

=23.

I hope this helps you