Which among the following is the strongest reducing agent?

Options

A. K
B. Na
C. Al
D. Mg

Answer

To determine which among the given elements is the strongest reducing agent, we will analyze the options step by step.

### Step 1: Understand the Concept of Reducing Agents
A reducing agent is a substance that loses electrons and, in the process, reduces another substance. The stronger the reducing agent, the more readily it loses electrons.

**Hint:** Remember that reducing agents undergo oxidation themselves while reducing another substance.

### Step 2: Identify the Elements and Their Groups
The options provided are:
- Option A: Potassium (K)
- Option B: Sodium (Na)
- Option C: Aluminum (Al)
- Option D: Magnesium (Mg)

Potassium and sodium are alkali metals (Group 1), while aluminum and magnesium are alkaline earth metals (Group 2).

**Hint:** Group 1 elements generally have a higher tendency to lose electrons compared to Group 2 elements.

### Step 3: Compare the Electron Configurations
- Alkali metals (K, Na) have the general electronic configuration of \( ns^1 \), meaning they have one electron in their outermost shell.
- Alkaline earth metals (Al, Mg) have the general electronic configuration of \( ns^2 \), meaning they have two electrons in their outermost shell.

**Hint:** The fewer the electrons in the outer shell, the easier it is for the element to lose them.

### Step 4: Analyze the Tendency to Lose Electrons
Alkali metals are more reactive than alkaline earth metals because they can lose their single outer electron more easily. Between potassium and sodium, we need to consider their positions in the periodic table.

**Hint:** Reactivity increases down the group in the periodic table.

### Step 5: Compare Potassium and Sodium
As we move down the group from sodium to potassium, the atomic size increases. A larger atomic size means that the outer electron is further away from the nucleus and is less tightly held, making it easier to lose.

**Hint:** Larger atoms tend to lose electrons more easily, increasing their reducing power.

### Step 6: Conclusion
Since potassium is below sodium in the periodic table, it has a greater tendency to lose its outer electron compared to sodium. Therefore, potassium is the strongest reducing agent among the given options.

**Final Answer:** Option A: Potassium (K) is the strongest reducing agent.