Question

follows Dobereiner's law of Triads.

• A. Sr, Ba, Ca
• B. Br, Cl, I
• C. Cl, Br, I

Answer 1

The correct option is C Cl, Br, I

Dobereiner's law of Triads:

(i) The elements are written in increasing order of atomic mass

(ii)The mass of middle element was roughly the average of atomic masses of other two elements

(iii) Elements in the Triads show similar properties.

Of the given options, you can deduce that only in one option, the elements are in the increasing order of their atomic mass and middle element was roughly the average of atomic masses of other two elements. Hence Cl, Br and I form Doberenier's triads.