Among `Al_(2)O_(3),SiO_(2),P_(2)O_(5) and SO_(3)` the correct order of acid strength is :-

Options

A. `Al_(2)O_(3)ltSiO_(2)ltSO_(3)ltP_(2)O_(5)`
B. `SiO_(2) lt SO_(3) lt Al_(2)O_(3) lt P_(2)O_(5)`
C. `SO_(3)ltP_(2)O_(5)ltSiO_(2)ltAl_(2)O_(3)`
D. `Al_(2)O_(3)ltSiO_(2)ltP_(2)O_(5)ltSO_(3)`

Answer

To determine the correct order of acid strength among Al₂O₃, SiO₂, P₂O₅, and SO₃, we need to analyze the acidic properties of each compound based on their oxidation states and electronegativities.

### Step-by-Step Solution:

1. **Understanding Acid Strength**:
- Acid strength is determined by the tendency of an acid to dissociate into cations and anions. The greater the tendency to dissociate, the stronger the acid.

2. **Identify Oxidation States**:
- Determine the oxidation states of the central atoms in each compound:
- **Al₂O₃**: Aluminum (Al) has an oxidation state of +3.
- **SiO₂**: Silicon (Si) has an oxidation state of +4.
- **P₂O₅**: Phosphorus (P) has an oxidation state of +5.
- **SO₃**: Sulfur (S) has an oxidation state of +6.

3. **Comparing Oxidation States**:
- The higher the oxidation state of the central atom, the stronger the acid. This is because a higher oxidation state typically indicates a greater ability to attract electrons, facilitating the release of protons (H⁺ ions).

4. **Electronegativity Consideration**:
- Electronegativity also plays a role in acid strength. The more electronegative the central atom, the stronger the acid. Sulfur is more electronegative than phosphorus, which is more electronegative than silicon and aluminum.

5. **Ranking the Compounds**:
- Based on the oxidation states and electronegativities, we can rank the compounds:
- **SO₃** (S in +6 oxidation state, highly electronegative) - Strongest acid
- **P₂O₅** (P in +5 oxidation state) - Second strongest
- **SiO₂** (Si in +4 oxidation state) - Weaker than P₂O₅
- **Al₂O₃** (Al in +3 oxidation state) - Amphoteric, thus weaker than SiO₂

6. **Final Order of Acid Strength**:
- The correct order of acid strength is: **SO₃ > P₂O₅ > SiO₂ > Al₂O₃**.

### Conclusion:
The correct order of acid strength among Al₂O₃, SiO₂, P₂O₅, and SO₃ is **SO₃ > P₂O₅ > SiO₂ > Al₂O₃**.