The correct order of acidic strength is

Options

A. `Cl_(2)O_(7) gt SO_(2) gtP_(4)O_(10)`
B. `CO_(2) gt N_(2)O_(5)gtSO_(3)`
C. `Na_(2)O gt MgO gt Al_(2)O_(3)`
D. `K_(2)O gt CaO gt MgO`

Answer

To determine the correct order of acidic strength among the given oxides, we will analyze the acidic character based on periodic trends.

### Step-by-Step Solution:

1. **Understand Acidic Strength**: Acidic strength of oxides generally depends on the electronegativity of the central atom and its position in the periodic table.

2. **Periodic Trends**:
- **Down a Group**: As we move down a group in the periodic table, the acidity of oxides generally decreases. This is because the size of the atoms increases, leading to a decrease in electronegativity and the ability to attract electrons.
- **Across a Period**: As we move from left to right across a period, the acidity of oxides generally increases. This is due to increasing electronegativity and decreasing atomic size, which enhances the ability to attract electrons.

3. **Analyze the Given Oxides**:
- **Option 1**: Cl2O7, SO2, P4O10
- Cl2O7 has chlorine, which is highly electronegative and is to the right in the periodic table, making it very acidic.
- SO2 has sulfur, which is less electronegative than chlorine but more than phosphorus.
- P4O10 has phosphorus, which is the least acidic of the three.
- **Order**: Cl2O7 > SO2 > P4O10 (Correct)

- **Option 2**: CO2, N2O5, SO3
- N2O5 is more acidic than CO2 because nitrogen is to the right of carbon in the same period.
- SO3 is more acidic than both CO2 and N2O5.
- **Order**: SO3 > N2O5 > CO2 (Incorrect as per the given order)

- **Option 3**: Na2O, MgO, Al2O3
- Al2O3 is more acidic than MgO and Na2O due to the higher electronegativity of aluminum compared to magnesium and sodium.
- **Order**: Al2O3 > MgO > Na2O (Incorrect as per the given order)

- **Option 4**: K2O, CaO, MgO
- MgO is the most acidic, followed by CaO, and then K2O.
- **Order**: MgO > CaO > K2O (Incorrect as per the given order)

4. **Conclusion**: Based on the analysis, the only correct order of acidic strength is found in Option 1: **Cl2O7 > SO2 > P4O10**.

### Final Answer:
The correct order of acidic strength is **Cl2O7 > SO2 > P4O10** (Option 1).

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