Alkali earth metals in liq. `NH_(3)` produce a blue coloured solution, due to

Options

A. Polarisability of `NH_(3)`
B. Charge transfer
C. `dto d` transition
D. Ammoniated electrons

Answer

To solve the question regarding why alkali earth metals in liquid ammonia produce a blue-colored solution, we can follow these steps:

### Step 1: Understanding the Reaction
When alkali earth metals (like sodium or potassium) react with liquid ammonia, they form a solution. The alkali earth metal donates an electron to the ammonia molecules.

**Hint:** Consider the nature of the alkali earth metals and their tendency to lose electrons.

### Step 2: Formation of Ammoniated Electrons
As the alkali earth metal donates an electron, it forms a positively charged ion (NH3X⁺) and a negatively charged ammoniated electron (NH3Y⁻). The ammoniated electron is essentially an electron that is surrounded by ammonia molecules.

**Hint:** Think about what happens to the electron when it interacts with the ammonia molecules.

### Step 3: Color of the Solution
The presence of these ammoniated electrons is what imparts the blue color to the solution. The blue color arises due to the absorption of certain wavelengths of light by the ammoniated electrons.

**Hint:** Reflect on how certain substances can absorb light and how this relates to color.

### Step 4: Conclusion
Thus, the blue color of the solution is due to the presence of ammoniated electrons formed when alkali earth metals react with liquid ammonia.

**Hint:** Summarize the key concept that relates the formation of ammoniated electrons to the observed color.

### Final Answer:
Alkali earth metals in liquid ammonia produce a blue-colored solution due to the formation of ammoniated electrons.