Give chemical composition of glassy bead .

Explanation

To determine the chemical composition of a glassy bead, we need to understand how it is formed from borax. Here is a step-by-step breakdown of the process:

### Step-by-Step Solution:

1. **Identify the Starting Material**: The starting material for creating a glassy bead is powdered borax, which has the chemical formula Na2B4O7·10H2O (sodium borate decahydrate).

2. **Heating the Borax**: When powdered borax is heated strongly in a Bunsen burner, it undergoes a thermal decomposition reaction. The water of crystallization is removed, and the borax decomposes.

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