Which of the following oxide is most acidic ?

Options

A. `Na_(2)O`
B. `Al_(2)O_(3)`
C. `P_(2)O_(5)`
D. `SO_(3)`

Answer

To determine which of the following oxides is the most acidic, we can use two different methods: oxidation state analysis and periodic trends. Let's go through the steps for both methods.

### Step-by-Step Solution:

**Step 1: Identify the Oxides**
First, we need to identify the oxides in question. For this example, let's assume the oxides are Na2O, P2O5, and SO3.

**Step 2: Calculate the Oxidation States**
Next, we will calculate the oxidation states of the central atoms in each oxide.

- For Na2O:
- Let the oxidation state of Na be \(X\).
- The equation becomes: \(2X - 2 = 0\)
- Solving for \(X\), we find \(X = +1\).

- For P2O5:
- Let the oxidation state of P be \(Y\).
- The equation becomes: \(2Y - 5 \times 2 = 0\)
- Solving for \(Y\), we find \(Y = +5\).

- For SO3:
- Let the oxidation state of S be \(Z\).
- The equation becomes: \(Z - 3 \times 2 = 0\)
- Solving for \(Z\), we find \(Z = +6\).

**Step 3: Determine Acidic Nature Based on Oxidation States**
The acidic nature of oxides generally increases with the oxidation state of the central atom.

- Na2O has an oxidation state of +1 (basic).
- P2O5 has an oxidation state of +5 (acidic).
- SO3 has an oxidation state of +6 (highly acidic).

**Step 4: Conclusion from Oxidation States**
From our calculations, SO3 has the highest oxidation state (+6), indicating that it is the most acidic oxide among the given options.

**Step 5: Confirm with Periodic Trends**
Additionally, we can confirm this conclusion using periodic trends. As we move from left to right across a period in the periodic table, the acidic nature of oxides tends to increase. Sodium (Na) is on the left, while sulfur (S) is on the right. Therefore, SO3, which contains sulfur, is expected to be more acidic than Na2O and P2O5.

### Final Answer:
The most acidic oxide among the given options is **SO3**.

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