Assertion (A): Alkali metals are strong reducing agents.
Reason (R ): They have only one electron to be lost form their valence shells.

Options

A. If both (A) and (R ) are correct and (R ) is the correct explanation of (A).
B. If both (A) and (R ) are correct, but (R ) is not the correct explanation of (A).
C. If (A) is correct, but (R ) is incorrect.
D. If (A) is incorrect, but (R ) is correct.

Answer

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

### Step 1: Understanding the Assertion
The assertion states that "Alkali metals are strong reducing agents."

**Explanation:**
Alkali metals (like lithium, sodium, potassium, etc.) are known for their ability to lose electrons easily. This is due to their low ionization energies, which means they require relatively little energy to remove an electron from their outer shell. When they lose an electron, they become positively charged ions (cations), which can then donate electrons to other substances, thereby reducing them.

### Step 2: Understanding the Reason
The reason states that "They have only one electron to be lost from their valence shells."

**Explanation:**
Alkali metals have a single electron in their outermost shell (valence shell). This configuration makes it energetically favorable for them to lose that one electron to achieve a stable noble gas configuration. The loss of this electron is what allows them to act as reducing agents, as they can easily donate this electron to other species.

### Step 3: Linking Assertion and Reason
Now, we need to connect the assertion and the reason.

**Explanation:**
The reason provided supports the assertion. Because alkali metals have only one electron in their valence shell, they can easily lose it, making them strong reducing agents. The ability to lose this electron readily is what characterizes their strong reducing nature.

### Conclusion
Both the assertion and the reason are correct, and the reason accurately explains why alkali metals are strong reducing agents.

### Final Answer
The correct answer is that both the assertion and the reason are true, and the reason is a correct explanation of the assertion.

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