In a Photochemical reaction, the ratio of number of dissociate molecules and number of quanta of absorbed energy is called

Options

A. Einstein
B. Quantum efficiency
C. Quantum constant
D. Planck constant

Explanation

To solve the question regarding the ratio of the number of dissociated molecules to the number of quanta of absorbed energy in a photochemical reaction, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Terms**:
- In photochemical reactions, molecules absorb energy in the form of light (quanta).
- When these molecules absorb enough energy, they can dissociate into products.

2. **Define the Ratio**:
- The ratio we are interested in is the number of molecules that dissociate (let's denote this as \( N_d \)) to the number of quanta of energy absorbed (denote this as \( N_q \)).
- Mathematically, this can be expressed as:
\[ \text{Ratio} = \frac{N_d}{N_q} \]

3. **Identify the Concept**:
- This ratio is a measure of the efficiency of the photochemical reaction.
- It indicates how many molecules dissociate for each quantum of energy absorbed.

4. **Name the Concept**:
- The term used to describe this ratio is "quantum efficiency" or "quantum yield".
- Quantum efficiency is denoted by the symbol \( \Phi \) (phi).

5. **Conclusion**:
- Therefore, in a photochemical reaction, the ratio of the number of dissociated molecules to the number of quanta of absorbed energy is called **quantum efficiency**.

### Final Answer:
The ratio of the number of dissociated molecules to the number of quanta of absorbed energy in a photochemical reaction is called **quantum efficiency**.

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