Borax is:

Options

A. `Na_(2)B_(4)O_(7)`
B. `Na_(2)B_(4)O_(7).4H_(2)O`
C. `Na_(2)B_(4)O_(7).7H_(2)O`
D. `Na_(2)B_(4)O_(7).10H_(2)O`

Answer

To answer the question "Borax is:", we can break down the information provided in the video transcript into a structured solution.

### Step-by-Step Solution:

1. **Identify Borax**: Borax is a chemical compound commonly known as sodium borate.

2. **Chemical Formula**: The chemical formula for Borax can be represented in two ways:
- Na2B4O5(OH)4·8H2O
- Na2B4O7·10H2O

3. **Understanding the Components**:
- **Na**: Sodium
- **B**: Boron
- **O**: Oxygen
- **H**: Hydrogen
- The formula indicates that Borax contains sodium, boron, oxygen, and water molecules.

4. **Structure**: The structure of Borax can be complex, but it generally consists of borate ions and sodium ions, along with water of crystallization.

5. **Conclusion**: Based on the information, Borax is identified as a hydrated sodium borate with the formula Na2B4O7·10H2O, making option D the correct choice.

### Final Answer:
Borax is Na2B4O7·10H2O (sodium tetraborate decahydrate).

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