Match List-I (coordination compound) with List-II (central metal atom).
| List-I | List-II |
| (A) Chlorophyll | (I) Rhodium |
| (B) Haemoglobin (blood pigment) | (II) Cobalt |
| (C) Wilkinson catalyst | (III) Iron |
| (D) Vitamin B12 | (IV) Magnesium |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → A-IV, B-III, C-I, D-II
Many compounds of biological and industrial importance are coordination compounds, each built round one central metal ion.
(A) Chlorophyll — This matches (IV) Magnesium. The green pigment of photosynthesis is a coordination compound of magnesium.
(B) Haemoglobin (blood pigment) — This matches (III) Iron. The red, oxygen-carrying pigment of blood is a coordination compound of iron.
(C) Wilkinson catalyst — This matches (I) Rhodium. It is the rhodium complex \( \ce{[(Ph3P)3RhCl]} \), used for the hydrogenation of alkenes.
(D) Vitamin B12 — This matches (II) Cobalt. Cyanocobalamine, the anti-pernicious anaemia factor, is a coordination compound of cobalt.
NCERT (2026-27 edition):
5.7 Importance and Applications of Coordination Compounds – “Coordination compounds are of great importance in biological systems. The pigment responsible for photosynthesis, chlorophyll, is a coordination compound of magnesium. Haemoglobin, the red pigment of blood which acts as oxygen carrier is a coordination compound of iron. Vitamin B12, cyanocobalamine, the anti– pernicious anaemia factor, is a coordination compound of cobalt.”
“Coordination compounds are used as catalysts for many industrial processes. Examples include rhodium complex, [(Ph3P)3RhCl], a Wilkinson catalyst, is used for the hydrogenation of alkenes.”