A metal M reaccts with nitrogen to give nitride which on reaction with water produces ammonia gas. Metal M can be

Options

A. Na
B. K
C. Li
D. Rb

Explanation

To solve the problem, we need to identify a metal \( M \) that reacts with nitrogen to form a nitride, which subsequently reacts with water to produce ammonia gas. Here’s a step-by-step breakdown of the solution:

### Step 1: Identify the Reaction with Nitrogen
We know that certain metals can react with nitrogen to form nitrides. Among the alkali metals, lithium is known to react with nitrogen.

**Hint:** Consider the reactivity of alkali metals with nitrogen.

### Step 2: Write the Reaction Equation
The reaction of lithium with nitrogen can be represented as:
\[ 3 \text{Li} + \text{N}_2 \rightarrow \text{Li}_3\text{N} \]
This shows that lithium combines with nitrogen to form lithium nitride.

**Hint:** Look for the stoichiometry of the reaction.

### Step 3: Reaction of Lithium Nitride with Water
Next, we need to consider what happens when lithium nitride reacts with water. The reaction can be written as:
\[ \text{Li}_3\text{N} + 3 \text{H}_2\text{O} \rightarrow 3 \text{NH}_3 + 3 \text{LiOH} \]
This indicates that lithium nitride reacts with water to produce ammonia gas and lithium hydroxide.

**Hint:** Think about the products formed when nitrides react with water.

### Step 4: Conclusion
From the above reactions, we can conclude that the metal \( M \) that reacts with nitrogen to form a nitride, which then produces ammonia upon reaction with water, is lithium.

**Final Answer:** The metal \( M \) can be lithium.