Which of the following has the highest normality ? ( consider each of the acid is 100% ionised )

Options

A. `1( M) H_(2) SO_(4)`
B. `1 ( M) H_(3) PO_(3)`
C. `1 ( M) H_(3) PO_(4)`
D. `1( M) HNO_(3)`

Explanation

To determine which of the given acids has the highest normality, we need to calculate the normality for each acid based on its ionization and the number of replaceable hydrogen ions (H⁺). Here's the step-by-step solution:

### Step 1: Understand Normality
Normality (N) is defined as the number of equivalents of solute per liter of solution. For acids, this is related to the number of replaceable H⁺ ions. The formula for normality is:
\[ \text{Normality (N)} = \text{Molarity (M)} \times n \]
where \( n \) is the number of replaceable H⁺ ions (also known as the n-factor).

### Step 2: Analyze Each Acid
We will analyze each acid given in the options to determine their n-factor and subsequently their normality.

1. **H₂SO₄ (Sulfuric Acid)**
- Ionization: H₂SO₄ → 2 H⁺ + SO₄²⁻
- Number of replaceable H⁺ ions = 2
- Assuming molarity (M) = 1, then:
\[ \text{Normality} = 1 \times 2 = 2 \, \text{N} \]

2. **H₃PO₃ (Phosphorous Acid)**
- Ionization: H₃PO₃ → 2 H⁺ + HPO₃²⁻
- Number of replaceable H⁺ ions = 2
- Assuming molarity (M) = 1, then:
\[ \text{Normality} = 1 \times 2 = 2 \, \text{N} \]

3. **H₃PO₄ (Phosphoric Acid)**
- Ionization: H₃PO₄ → 3 H⁺ + PO₄³⁻
- Number of replaceable H⁺ ions = 3
- Assuming molarity (M) = 1, then:
\[ \text{Normality} = 1 \times 3 = 3 \, \text{N} \]

4. **HNO₃ (Nitric Acid)**
- Ionization: HNO₃ → H⁺ + NO₃⁻
- Number of replaceable H⁺ ions = 1
- Assuming molarity (M) = 1, then:
\[ \text{Normality} = 1 \times 1 = 1 \, \text{N} \]

### Step 3: Compare Normalities
Now we have calculated the normalities for all the acids:
- H₂SO₄: 2 N
- H₃PO₃: 2 N
- H₃PO₄: 3 N
- HNO₃: 1 N

### Conclusion
The acid with the highest normality is **H₃PO₄ (Phosphoric Acid)** with a normality of **3 N**.