Question

The empirical formula of chlorophyll a is:
A. ${C}_{55}{H}_{72}{O}_{5}{N}_{4}Mg$
B. ${C}_{55}{H}_{70}{O}_{6}{N}_{4}Mg$
C. ${C}_{55}{H}_{72}{O}_{5}{N}_{4}Fe$
D. ${C}_{55}{H}_{72}{O}_{4}{N}_{5}Mg$

Answer 1

Hint Chlorophyll is the pigment that is involved in the process of photosynthesis. It is responsible for the green color of the leaves. Chlorophyll a is a specific form of chlorophyll.

Complete answer:
- Chlorophyll a is an odorless compound that is insoluble in water.
- Chlorophylls are cyclic tetrapyrrole structures.
- They have a porphyrin head and a long phytol tail attached to the head.
- In the structure of the chlorophyll a, one atom of magnesium is coordinated to the cyclic tetrapyrrole.
- It is used in oxygenic photosynthesis.
- It is known to absorb most of the energy from the wavelengths of violet-blue and red-orange-red light.
- It also contributes to the green color of most of the plants by reflecting green-yellow light.
- Chlorophyll a is very essential for photosynthesis in eukaryotes, cyanobacteria, and prochlorophytes.
- This is due to the reason that it acts as the primary electron donor in the electron transport chain.
- The molecular structure of chlorophyll a has a chlorin ring, whose four nitrogen atoms surround the magnesium atom which is the central atom and has several other side chains and a hydrocarbon tail.
- The chemical formula of chlorophyll a is ${C}_{55}{H}_{72}{O}_{5}{N}_{4}Mg$.

Hence, option (A) is the correct option.

Note: Chlorophyll a is very soluble in ethanol and ether. It is soluble in acetone, benzene, and chloroform. It is commonly found in wheat. It is used in food processing as a control agent for colors.