The law of triads is applicable to a group of - Sri Chaitanya Infinity Learn Best Online Courses for NCERT Solutions, CBSE, ICSE, JEE, NEET, Olympiad and Class 6 to 12

Cl, Br, I follow law of triads.

Atomic weight of $C l = 35.5$ .

Atomic weight of $Br = 80.0$

Atomic weight of $I = 127$

According to law of triads the arithmetic mean of first and third elements is equal to atomic weight of middle element.

Arithmetic mean of $C l and I = \frac{35.5 + 127}{2}$ $= 81.25$

So, Cl, Br, I nearly follows law of triads.

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