Which of the following statements are false?

Options

A. `BeCl_(2)` exists as dimer in the vapour state and polymeric in the solid state.
B. Calcium hydride is called hydrolith.
C. The oxides of `Be` and `Ca` are amphoteric.
D. Bicarbonates of `Na` and `Sr` are insoluble in water.

Explanation

To determine which statements are false regarding the properties of certain compounds related to alkaline earth metals, we can analyze each statement one by one.

### Step-by-Step Solution:

1. **Evaluate Statement 1:**
- **Statement:** BeCl2 exists as a dimer in the vapor state and polymeric in the solid state.
- **Analysis:** Beryllium chloride (BeCl2) does indeed exist as a dimer (Be2Cl4) in the vapor state and forms a polymeric structure in the solid state. This statement is **true**.

2. **Evaluate Statement 2:**
- **Statement:** Calcium hydride is called hydrolith.
- **Analysis:** Calcium hydride (CaH2) is commonly known as hydrolith. This statement is also **true**.

3. **Evaluate Statement 3:**
- **Statement:** Oxides of beryllium and calcium are amphoteric in nature.
- **Analysis:** Beryllium oxide (BeO) is amphoteric, meaning it can react with both acids and bases. However, calcium oxide (CaO) is basic and not amphoteric. Therefore, this statement is **false**.

4. **Evaluate Statement 4:**
- **Statement:** Bicarbonate of sodium and strontium are insoluble in water.
- **Analysis:** Sodium bicarbonate (NaHCO3) is soluble in water, while strontium bicarbonate (Sr(HCO3)2) is generally considered to be less soluble. Thus, the statement that both are insoluble is **false**.

### Conclusion:
The false statements are:
- Statement 3: Oxides of beryllium and calcium are amphoteric in nature (false because CaO is basic).
- Statement 4: Bicarbonate of sodium and strontium are insoluble in water (false because NaHCO3 is soluble).

Thus, the correct answer is that statements **C and D** are false.