The dilute solutions of which of the following are not harmful to drink ?
A. Magnesium hydroxide
B. Potassium hydroxide
C. Sodium hydrogencarbonate
D. Sodium carbonate

Options

A. A and B
B. B and C
C. A and C
D. B and D

Answer

To determine which dilute solutions are not harmful to drink among the given options, we need to analyze the nature of each compound and their effects on the human body when consumed in dilute form.

### Step-by-Step Solution:

1. **Understanding the Compounds**:
- **Magnesium Hydroxide (Mg(OH)₂)**: This is a common antacid used to neutralize stomach acidity.
- **Potassium Hydroxide (KOH)**: This is a strong base and can be very alkaline.
- **Sodium Hydrogencarbonate (NaHCO₃)**: Also known as baking soda, it is commonly used as an antacid.
- **Sodium Carbonate (Na₂CO₃)**: Known as washing soda, it is also a strong base and very alkaline.

2. **Analyzing Each Option**:
- **A. Magnesium Hydroxide**: It is safe to drink in dilute form as it acts as an antacid and is not very alkaline.
- **B. Potassium Hydroxide**: This is harmful to drink even in dilute form due to its high alkalinity, which can cause irritation and burning sensations.
- **C. Sodium Hydrogencarbonate**: This is also safe to drink in dilute form as it helps neutralize stomach acidity and is not highly alkaline.
- **D. Sodium Carbonate**: This is harmful to drink because it is very alkaline and can cause burning in the throat.

3. **Conclusion**:
- The dilute solutions that are not harmful to drink are **A. Magnesium Hydroxide** and **C. Sodium Hydrogencarbonate**.

### Final Answer:
The dilute solutions of which of the following are not harmful to drink?
**A. Magnesium Hydroxide and C. Sodium Hydrogencarbonate**.

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