Question

Primary valency of $Co$ in $[Co(en)_2Cl_2]\, Cl$ is

• A. $+1$
• B. $+2$
• C. $+3$
• D. $+6$

Answer 1

Answer: (C)

Primary valency is the oxidation state of the central metal ion.
Let, oxidation state of $Co$ in $[Co(en)_2Cl_2] Cl$ be $x$.
$x +2 (0 ) + 2 (-1) - 1 = 0$
$\therefore x= + 3$
$\therefore$ Primary valency of $Co = + 3$