`Ca_(2)B_(6)O_(11)+2Na_(2)CO_(3)to X+2CaCO_(3)+2NaBO_(2)` The compound X in the above reaction is

Options

A. `Na_(2)B_(4)O_(7)`
B. `HBO_(2)`
C. `H_(3)BO_(3)`
D. `H_(2)B_(4)O_(7)`

Explanation

To solve the question regarding the reaction of \( Ca_2B_6O_{11} \) with \( 2Na_2CO_3 \) to find the compound \( X \), we can follow these steps:

### Step 1: Write the balanced chemical equation
The reaction can be written as follows:
\[ Ca_2B_6O_{11} + 2Na_2CO_3 \rightarrow X + 2CaCO_3 + 2NaBO_2 \]

### Step 2: Identify the reactants and products
- **Reactants**: \( Ca_2B_6O_{11} \) (calcium borate) and \( 2Na_2CO_3 \) (sodium carbonate).
- **Products**: \( 2CaCO_3 \) (calcium carbonate) and \( 2NaBO_2 \) (sodium metaborate).

### Step 3: Determine the nature of compound \( X \)
In this reaction, \( X \) is formed along with the other products. The formation of sodium metaborate suggests that \( X \) is likely a sodium borate compound.

### Step 4: Recognize the formation of borax
The reaction is known to produce borax, which has the formula \( Na_2B_4O_7 \). This is a common product when sodium carbonate reacts with boron compounds.

### Step 5: Conclude the identity of compound \( X \)
Thus, the compound \( X \) in the reaction is:
\[ X = Na_2B_4O_7 \quad \text{(borax)} \]

### Final Answer
The compound \( X \) in the reaction is **borax** (\( Na_2B_4O_7 \)).

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