A : Lithium is less reactive but the strogest reducing agent in aqueous solution.
R : Lithium shows positive reduction potential.

Options

A. If both Assertion & Reason are true and the reason is the correct explanantion of the assertion, then mark (1).
B. If both Assertion & Reason are true and the reason is the correct explanantion of the assertion, then mark (2).
C. If Assertion is true statement but Reason is false. Them mark (3).
D. If both Assertion and reason are false statement, then mark (4).

Answer

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

### Step 1: Understanding the Assertion
The assertion states that "Lithium is less reactive but the strongest reducing agent in aqueous solution."
- Lithium is indeed less reactive compared to other alkali metals like sodium or potassium due to its high ionization energy. This means it does not easily lose its outermost electron when in solution.

**Hint:** Consider the reactivity series of metals and how ionization energy affects reactivity.

### Step 2: Understanding Reducing Agents
A reducing agent is a substance that donates electrons to another species, thereby reducing that species.
- Despite lithium's high ionization energy, it can still act as a strong reducing agent in aqueous solution because of its ability to donate electrons once it is hydrated.

**Hint:** Recall the definition of reducing agents and how they function in chemical reactions.

### Step 3: Role of Hydration Energy
In aqueous solution, lithium experiences high hydration energy, which compensates for its high ionization energy.
- Hydration energy is the energy released when ions are surrounded by water molecules. For lithium, this energy is significant enough to allow it to donate its electron.

**Hint:** Think about how hydration energy influences the stability of ions in solution.

### Step 4: Analyzing the Reason
The reason states that "Lithium shows positive reduction potential."
- This statement is incorrect. In fact, lithium has a negative standard reduction potential of about -3.0 volts, indicating that it is not favorable for lithium to gain electrons (i.e., it does not have a positive reduction potential).

**Hint:** Review the concept of reduction potential and how it is measured.

### Step 5: Conclusion
From the analysis:
- The assertion is true: Lithium is less reactive but is a strong reducing agent in aqueous solution.
- The reason is false: Lithium does not show a positive reduction potential.

Thus, the correct conclusion is that the assertion is true, but the reason is false.

**Final Answer:** The assertion is true, and the reason is false.