Identify the incorrect formula among the following.

Options

A. `Mg_(2)O`
B. ZnO
C. CaO
D. `SO_(3)`

Explanation

To identify the incorrect formula among the given options, we will analyze each formula step by step.

### Step 1: Analyze Magnesium Oxide (MgO)
- **Formula Given:** Mg2O
- **Valency of Magnesium (Mg):** +2
- **Valency of Oxygen (O):** -2
- **Correct Formula:**
- Since Magnesium has a +2 charge and Oxygen has a -2 charge, they combine in a 1:1 ratio. Therefore, the correct formula for Magnesium Oxide is **MgO**.
- **Conclusion:** Mg2O is incorrect.

### Step 2: Analyze Zinc Oxide (ZnO)
- **Formula Given:** ZnO
- **Valency of Zinc (Zn):** +2
- **Valency of Oxygen (O):** -2
- **Correct Formula:**
- Zinc also has a +2 charge and Oxygen has a -2 charge, which means they combine in a 1:1 ratio. The correct formula for Zinc Oxide is **ZnO**.
- **Conclusion:** ZnO is correct.

### Step 3: Analyze Calcium Oxide (CaO)
- **Formula Given:** CaO
- **Valency of Calcium (Ca):** +2
- **Valency of Oxygen (O):** -2
- **Correct Formula:**
- Calcium has a +2 charge and Oxygen has a -2 charge, which means they combine in a 1:1 ratio. The correct formula for Calcium Oxide is **CaO**.
- **Conclusion:** CaO is correct.

### Step 4: Analyze Sulfur Trioxide (SO3)
- **Formula Given:** SO3
- **Valency of Sulfur (S):** +6 (in this case)
- **Valency of Oxygen (O):** -2
- **Correct Formula:**
- Sulfur can have a +6 charge and Oxygen has a -2 charge. In SO3, one Sulfur atom combines with three Oxygen atoms, which balances the charges. Therefore, the correct formula for Sulfur Trioxide is **SO3**.
- **Conclusion:** SO3 is correct.

### Final Conclusion
Among the given formulas, the incorrect formula is **Mg2O**. The correct formula for Magnesium Oxide is **MgO**.

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