What happen when a mixture of cobalt oxide and borax is heated in a flame on a loop of platinum wire?

Options

A. A transparent white heat is formed
B. A bright pind coloured `NaBO_(2)` bead is formed.
C. A blue coloured `Co(BO_(2))_(2)` bead is formed
D. A red coloured `CO(BO_(2))_(2)` bead is formed.

Explanation

To solve the question regarding what happens when a mixture of cobalt oxide and borax is heated in a flame on a loop of platinum wire, we can break it down into a series of steps:

### Step-by-Step Solution:

1. **Understanding the Components**:
- We have cobalt oxide (CoO) and borax (sodium borate, Na2B4O7·10H2O) as our starting materials.

2. **Heating Borax**:
- When borax is heated, it loses water molecules and dehydrates to form anhydrous sodium borate (Na2B4O7).

**Hint**: Remember that borax is a hydrate, and heating it will remove water.

3. **Further Heating of Anhydrous Borate**:
- Upon further heating, the anhydrous sodium borate can decompose to form sodium metaborate (NaBO2) and boric oxide (B2O3).

**Hint**: Look for decomposition reactions when substances are heated.

4. **Reaction with Cobalt Oxide**:
- The boric oxide (B2O3) formed can react with cobalt oxide (CoO) to produce cobalt metaborate (Co(BO2)2).

**Hint**: Identify how metal oxides react with boron compounds.

5. **Color of the Product**:
- Cobalt metaborate is known to have a blue color.

**Hint**: Pay attention to the characteristic colors of metal borates.

6. **Choosing the Correct Option**:
- Based on the reactions and the final product, the correct answer among the options provided is that a blue-colored cobalt metaborate bead is formed.

**Hint**: Match the final product's color with the options given.

### Conclusion:
When a mixture of cobalt oxide and borax is heated in a flame on a loop of platinum wire, a blue-colored cobalt metaborate bead is formed.

### Final Answer:
**A blue colored cobalt metaborate bead is formed.**

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