Which of the following statements about $[Co (en) X_{2} Cl X_{2}] X^{+}$ (octahedral, en $=$ ethane-1,2-diamine, bidentate) are correct? Use EAN $= Z - oxidation state + 2 \times$ number of donor atoms, with $Z (Co) = 27$ .

AThe EAN of cobalt is 36.
BIt has two geometrical isomers.
CThe cis form is optically active.
DThe trans form is optically active.

Answer: A, B, C

Co is

+ 3

(en neutral, two

Cl X^{-}

, overall

+ 1

). Donor atoms are 6, so EAN

= 27 - 3 + 12 = 36

. The cis and trans forms are the two geometrical isomers; the cis form lacks a mirror plane and exists as an enantiomeric pair (3 stereoisomers in all), while trans has mirror planes and is achiral.

Practice Coordination Compounds More on Terminology, ligands and denticity, EAN

Previous questionNext question

Which of the following statements about [Co(en)X2​ClX2​]X+ (octahedral, en = ethane-1,2-diamine, bidentate) are correct? Use EAN =Z−oxidation state+2× number of donor atoms, with Z(Co)=27.

Answer: A, B, C

More questions on Terminology, ligands and denticity, EAN

Which of the following statements about $[Co (en) X_{2} Cl X_{2}] X^{+}$ (octahedral, en $=$ ethane-1,2-diamine, bidentate) are correct? Use EAN $= Z - oxidation state + 2 \times$ number of donor atoms, with $Z (Co) = 27$ .