Which of the following statements is/are correct?

Options

A. `NaHCO_(3)` is more soluble than `Na_(2)CO_(3)`
B. `NaOH` is known as caustic soda
C. `NaHCO_(3)` is used as an antacid
D. `Na_(2)CO_(3)` is used in the manufacturing of soap and glass

Answer

To determine which of the given statements about sodium compounds are correct, we will analyze each statement one by one.

### Step 1: Analyze Statement A
**Statement A:** Sodium hydrogen carbonate is more soluble than sodium carbonate.

- **Analysis:** Sodium hydrogen carbonate (NaHCO₃) is less soluble than sodium carbonate (Na₂CO₃). Sodium carbonate is more soluble in water because it does not contain the bicarbonate ion, which requires higher temperatures to dissolve. Therefore, this statement is **incorrect**.

### Step 2: Analyze Statement B
**Statement B:** Sodium hydroxide is known as caustic soda.

- **Analysis:** Sodium hydroxide (NaOH) is indeed known as caustic soda. The term "caustic" refers to its ability to burn living tissues. Therefore, this statement is **correct**.

### Step 3: Analyze Statement C
**Statement C:** Sodium hydrogen carbonate is used as an antacid.

- **Analysis:** Sodium hydrogen carbonate (NaHCO₃), also known as baking soda, is commonly used as an antacid. It neutralizes stomach acidity, making this statement **correct**.

### Step 4: Analyze Statement D
**Statement D:** Sodium carbonate is used in the manufacturing of soap and glass.

- **Analysis:** Sodium carbonate (Na₂CO₃) is not used in the manufacturing of soap and glass; instead, sodium hydroxide (NaOH) is primarily used for these purposes. Therefore, this statement is **incorrect**.

### Conclusion
Based on the analysis of each statement:
- **Correct Statements:** B and C
- **Incorrect Statements:** A and D

### Final Answer
The correct statements are:
- B: Sodium hydroxide is known as caustic soda.
- C: Sodium hydrogen carbonate is used as an antacid.

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