Select incorrect statement:

Options

A. `Li_(2)CO_(3)` is only sparingly soluble in water and no `LiHCO_(3)` has been process
B. `K_(2)CO_(3)` can not be made by a method similar to the solvey process
C. `Li_(2)CO_(3) and MgCO_(3)` both are thermally stable
D. `Na_(2)CO_(3), NaHCO_(3)*2H_(2)O` is a mineral called trona

Answer

To solve the question of identifying the incorrect statement regarding the properties of certain compounds, we will analyze each statement one by one.

### Step 1: Analyze the first statement
**Statement:** "Li2CO3 is only sparingly soluble in water and no LiHCO3 has been processed."

**Analysis:**
- Lithium carbonate (Li2CO3) is indeed sparingly soluble in water. This is due to the strong electrostatic attraction between the small lithium cation and the carbonate anion, which overcomes the attraction between these ions and water molecules.
- Additionally, lithium bicarbonate (LiHCO3) does exist but is less commonly processed or encountered compared to other bicarbonates.

**Conclusion:** This statement is correct.

### Step 2: Analyze the second statement
**Statement:** "K2CO3 cannot be made by method similar to the Solvay process."

**Analysis:**
- Potassium carbonate (K2CO3) is soluble in water and does not precipitate when carbon dioxide is passed through a solution of potassium chloride and sodium bicarbonate. Therefore, the Solvay process, which is effective for sodium carbonate production, cannot be applied to potassium carbonate.

**Conclusion:** This statement is correct.

### Step 3: Analyze the third statement
**Statement:** "Li2CO3 and MgCO3 both are thermally stable."

**Analysis:**
- This statement is incorrect. Both lithium carbonate (Li2CO3) and magnesium carbonate (MgCO3) are thermally unstable. They decompose upon heating to produce carbon dioxide and their respective oxides (Li2O and MgO). The thermal instability is attributed to the large size difference and the covalent character of the carbonate ions.

**Conclusion:** This statement is incorrect.

### Step 4: Analyze the fourth statement
**Statement:** "Na2CO3, NaHCO3.2H2O is a mineral called Trona."

**Analysis:**
- This statement is correct. Trona is indeed a mineral that consists of hydrated sodium carbonate and sodium bicarbonate. It is commonly found in saline lake deposits and is an important source of sodium carbonate.

**Conclusion:** This statement is correct.

### Final Answer
The incorrect statement is: **"Li2CO3 and MgCO3 both are thermally stable."**

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