the empirical formula for chlorophyll a is

Options

A. `C_(35) H_(72) O_(5) N_(4) Mg`
B. `C_(65) H_(70) O_(6) N_(4) Mg`
C. `C_(55) H_(72) O_(5) N_(4) Mg`
D. `C_(45) H_(70) O_(6) N_(4) Mg`

Answer

To determine the empirical formula for chlorophyll A, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Molecular Formula**:
The molecular formula for chlorophyll A is given as C₅₅H₇₂O₅N₄Mg.

2. **Count the Atoms**:
From the molecular formula, we can count the number of each type of atom:
- Carbon (C): 55
- Hydrogen (H): 72
- Oxygen (O): 5
- Nitrogen (N): 4
- Magnesium (Mg): 1

3. **Determine the Greatest Common Divisor (GCD)**:
To find the empirical formula, we need to simplify the molecular formula by dividing the number of atoms of each element by their greatest common divisor. In this case, the GCD for the numbers 55, 72, 5, 4, and 1 is 1, since they do not share any common factors other than 1.

4. **Write the Empirical Formula**:
Since the GCD is 1, the empirical formula is the same as the molecular formula. Therefore, the empirical formula for chlorophyll A is C₅₅H₇₂O₅N₄Mg.

5. **Select the Correct Option**:
Based on the information provided, the correct option for the empirical formula of chlorophyll A is option 3.

### Final Answer:
The empirical formula for chlorophyll A is C₅₅H₇₂O₅N₄Mg.