select the correct statement:

Options

A. Lithium carbonate is insoluble in water.
B. Potassium carbonate is soluble in water.
C. Barium carbonate is soluble in water.
D. Lithium bicarbonate is insoluble in water.

Answer

To solve the question, we need to evaluate each of the given statements regarding the solubility of different carbonates in water. Let's analyze each option step by step:

### Step 1: Evaluate Option A
**Statement**: Lithium carbonate is insoluble in water.
**Analysis**: Lithium carbonate (Li2CO3) is actually sparingly soluble in water. Therefore, this statement is incorrect.

### Step 2: Evaluate Option B
**Statement**: Potassium carbonate is soluble in water.
**Analysis**: Potassium carbonate (K2CO3) is known to be soluble in water due to its ionic nature and the relatively large size of the potassium ion, which allows it to dissolve easily. Therefore, this statement is correct.

### Step 3: Evaluate Option C
**Statement**: Barium carbonate is soluble in water.
**Analysis**: Barium carbonate (BaCO3) is not soluble in water. In fact, the solubility of alkaline earth metal carbonates decreases down the group, and barium carbonate is known to be insoluble. Thus, this statement is incorrect.

### Step 4: Evaluate Option D
**Statement**: Lithium bicarbonate is insoluble in water.
**Analysis**: Lithium bicarbonate (LiHCO3) is also sparingly soluble in water. Therefore, this statement is incorrect.

### Conclusion
After evaluating all options, we find that the only correct statement is **Option B: Potassium carbonate is soluble in water**.

### Final Answer
The correct statement is **Option B**.

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