Assertion : Alkali metals are most suitable for photoelectric effect.
Reason : The work function of alkali metals is small, so even the radiations of small energy are able to cause the photoelectric effect.

Options

A. Assertion is True, Reason is True,
Reason is a correct explanation for Assertion.
B. Assertion is True, Reason is True,
Reason is not a correct explanation for Assertion.
C. Assertion is True, Reason is False.
D. Assertion is False but, Reason is True.

Answer

To analyze the assertion and reason provided in the question, we can break down the concepts involved step by step.

### Step 1: Understand the Assertion
**Assertion:** Alkali metals are most suitable for the photoelectric effect.

- **Explanation:** The photoelectric effect is the phenomenon where electrons are emitted from a material when it is exposed to light or electromagnetic radiation of sufficient energy. Alkali metals, such as lithium, sodium, and potassium, are known for their low ionization energies, which makes them good candidates for this effect.

### Step 2: Understand the Reason
**Reason:** The work function of alkali metals is small, so even the radiations of small energy are able to cause the photoelectric effect.

- **Explanation:** The work function is the minimum energy required to remove an electron from the surface of a material. For alkali metals, this work function is relatively low compared to other metals. This means that even photons with lower energy (longer wavelengths) can provide enough energy to overcome this work function and cause the emission of electrons.

### Step 3: Correlate Assertion and Reason
- The assertion states that alkali metals are suitable for the photoelectric effect, and the reason provided explains why this is the case. Since the work function of alkali metals is small, it allows for the emission of electrons with lower energy radiation, supporting the assertion.

### Step 4: Conclusion
- Both the assertion and the reason are correct, and the reason provides a valid explanation for the assertion. Therefore, we can conclude that the statement is true.

### Final Answer:
- **Assertion:** True
- **Reason:** True
- **Explanation:** The reason explains the assertion correctly.

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