Valency of nitrogen in ammonia, hydrogen in methane, sodium in sodium oxide and fluorine in fluorine gas are respectively

Options

A. 2, 1, 2 and 0
B. 3, 1, 1 and 1
C. 2, 2, 1 and 1
D. 3, 2, 2 and 1

Answer

To determine the valency of nitrogen in ammonia, hydrogen in methane, sodium in sodium oxide, and fluorine in fluorine gas, we can follow these steps:

### Step 1: Valency of Nitrogen in Ammonia (NH₃)
1. **Identify the oxidation states**: In ammonia (NH₃), hydrogen has an oxidation state of +1.
2. **Set up the equation**: Let the oxidation state of nitrogen be \( x \). The equation based on the total charge being zero is:
\[ x + 3(+1) = 0 \]
3. **Solve for \( x \)**:
\[ x + 3 = 0 \implies x = -3 \]
4. **Conclusion**: The valency of nitrogen in ammonia is 3.

### Step 2: Valency of Hydrogen in Methane (CH₄)
1. **Identify the oxidation states**: In methane (CH₄), carbon is more electronegative than hydrogen.
2. **Set up the equation**: Let the oxidation state of carbon be \( x \). The equation is:
\[ x + 4(+1) = 0 \]
3. **Solve for \( x \)**:
\[ x + 4 = 0 \implies x = -4 \]
4. **Conclusion**: The valency of hydrogen in methane is 1.

### Step 3: Valency of Sodium in Sodium Oxide (Na₂O)
1. **Identify the oxidation states**: In sodium oxide (Na₂O), oxygen has an oxidation state of -2.
2. **Set up the equation**: Let the oxidation state of sodium be \( x \). The equation is:
\[ 2x + (-2) = 0 \]
3. **Solve for \( x \)**:
\[ 2x - 2 = 0 \implies 2x = 2 \implies x = +1 \]
4. **Conclusion**: The valency of sodium in sodium oxide is 1.

### Step 4: Valency of Fluorine in Fluorine Gas (F₂)
1. **Identify the oxidation states**: Fluorine gas (F₂) consists of two fluorine atoms.
2. **Set up the equation**: Since it is a diatomic molecule, the oxidation state of each fluorine atom is 0.
3. **Conclusion**: The valency of fluorine in fluorine gas is 0.

### Final Answer:
- Valency of nitrogen in ammonia: **3**
- Valency of hydrogen in methane: **1**
- Valency of sodium in sodium oxide: **1**
- Valency of fluorine in fluorine gas: **0**

### Summary of Valencies:
- Nitrogen in NH₃: **3**
- Hydrogen in CH₄: **1**
- Sodium in Na₂O: **1**
- Fluorine in F₂: **0**