Which of the following will not act as antacid ?

Options

A. Sodium hydrogencarbonate
B. Magnesium hydroxide
C. Sodium carbonate
D. Aluminium carbonate

Answer

To determine which of the following substances will not act as an antacid, we need to understand what antacids are and how they function. Antacids are substances that neutralize stomach acidity, providing relief from discomfort caused by excess gastric acid.

### Step-by-Step Solution:

1. **Understanding Antacids**: Antacids are compounds that help neutralize stomach acid. They work by raising the pH level in the stomach, which alleviates symptoms of heartburn and indigestion.

2. **Identifying Common Antacids**: Common antacids include:
- Sodium Bicarbonate (NaHCO3)
- Magnesium Hydroxide (Mg(OH)2)
- Aluminum Hydroxide (Al(OH)3)

3. **Analyzing the Options**:
- **Sodium Bicarbonate (NaHCO3)**: This is a well-known antacid that neutralizes stomach acid effectively.
- **Magnesium Hydroxide (Mg(OH)2)**: This is also an effective antacid used to relieve indigestion and heartburn.
- **Sodium Carbonate (Na2CO3)**: This compound, commonly known as washing soda, is not suitable for use as an antacid. It can cause irritation and damage to the stomach lining if ingested.
- **Aluminum Hydroxide (Al(OH)3)**: This is another common antacid that helps to neutralize stomach acid.

4. **Conclusion**: Among the options provided, Sodium Carbonate (Na2CO3) is the substance that will not act as an antacid due to its potential to harm the stomach lining.

### Final Answer:
Sodium Carbonate (Na2CO3) will not act as an antacid.

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