Alkali metals cannot be extracted by reduction of their oxides and other compounds because

Options

A. alkali metals are strong reducing agents
B. alkali metals have low ionisation enthalpy
C. alkali metals have high latice enthalpy
D. alkali metals are strongly basic in nature.

Answer

**Step-by-Step Solution:**

1. **Understanding the Oxide of Alkali Metals:**
Alkali metals, represented as \( M \), form oxides generally in the form of \( M_2O \). In this oxide, \( M \) exists as \( M^+ \) ions and \( O^{2-} \) ions.

2. **Reduction Process:**
To extract the alkali metal from its oxide, the \( M^+ \) ion must be reduced to the neutral metal \( M \). This involves gaining an electron:
\[ M^+ + e^- \rightarrow M \]

3. **Stability of \( M^+ \) Ion:**
The \( M^+ \) ion is stable due to its noble gas configuration. Alkali metals have an electronic configuration of \( ns^1 \), where \( n \) is the outermost shell. When they lose one electron, they achieve a stable noble gas configuration as \( M^+ \).

4. **Inability to Gain an Electron:**
Since \( M^+ \) already has a stable configuration, it does not favorably accept an electron to revert to \( M \). Gaining an electron would disrupt this stable configuration and revert it back to a less stable state.

5. **Conclusion:**
Therefore, alkali metals cannot be extracted by reduction of their oxides because the \( M^+ \) ion is stable and does not readily gain an electron to form the neutral metal \( M \).

6. **Answer:**
The correct reason is that alkali metals are strong reducing agents. They readily lose an electron to form \( M^+ \) and cannot be reduced back to \( M \) from \( M^+ \).

**Final Answer:**
Alkali metals cannot be extracted by reduction of their oxides and other compounds because they are strong reducing agents and their \( M^+ \) ions are stable due to having a noble gas configuration.

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