Which of the following statements is/are true for the solutions of alkali metals and alkaline earth metals in ammonia (l) ?

Options

A. Concentrated solutions of alkali metals in ammonia are copper bronzed coloured and have a metallic lusture
B. Dilute solutions of alkaline earth metals are deep blue-black in colour due to the spectrum from the solvated electron
C. Concentrated solutions of the alkaline earth metals in ammonia are bronze coloured
D. Evaporation of the ammonia from solutions of alkali metals yields the metal , but with alkaline earth metals evaporation of ammonia gives hexammoniaes of the metals.

Explanation

To determine which statements are true regarding the solutions of alkali metals and alkaline earth metals in liquid ammonia, let's analyze each statement step by step.

### Step-by-Step Solution:

1. **Statement A**: "Concentrated solutions of alkali metals in ammonia are copper bronze color and have metallic luster."
- When alkali metals dissolve in liquid ammonia, they form solvated cations and solvated electrons. In dilute solutions, the color is blue due to the solvated electrons. As the concentration increases, the color changes to a bronze color, and the solution exhibits metallic luster.
- **Conclusion**: Statement A is **true**.

2. **Statement B**: "Dilute solutions of alkaline earth metals are deep blue-black in color due to the spectrum from the solvated electrons."
- Alkaline earth metals also react with liquid ammonia to form solvated cations. In dilute solutions, these can appear as deep blue or dark blue due to the presence of solvated electrons.
- **Conclusion**: Statement B is **true**.

3. **Statement C**: "Concentrated solutions of alkaline earth metals in ammonia are bronze colored."
- Similar to alkali metals, concentrated solutions of alkaline earth metals in ammonia can also exhibit a bronze color due to the concentration of solvated electrons and cations.
- **Conclusion**: Statement C is **true**.

4. **Statement D**: "Evaporation of ammonia from the solution of alkali metals gives the metal, but with alkaline earth metals, evaporation of ammonia gives the hexa-ammoniates of the metals."
- When ammonia evaporates from alkali metal solutions, the metal is recovered. However, for alkaline earth metals, the evaporation leads to the formation of hexa-ammoniates, which are complexes of the metal with ammonia.
- **Conclusion**: Statement D is **true**.

### Final Conclusion:
All statements A, B, C, and D are **true** for the solutions of alkali metals and alkaline earth metals in liquid ammonia.