Question

Which of the following set of elements cannot be a triad?

• A. $Li,Na,K$
• B. $B,Al,Ga$
• C. $Be,Mg,Ca$
• D. $Cl,Br,I$

Answer 1

Answer: (B)

$B,Al$ and $Ga$ are not a triad because the atomic weight of $Al$ is not equal to average atomic weight of $B$ and $Ga$