What is meant by oxy-hydrogen flame? For what purpose is it used?

Explanation

### Step-by-Step Solution:

1. **Definition of Oxy-Hydrogen Flame**:
- An oxy-hydrogen flame is produced when hydrogen gas (H2) is burned in the presence of oxygen gas (O2). The combustion reaction between hydrogen and oxygen generates a flame.

2. **Temperature of the Oxy-Hydrogen Flame**:
- The oxy-hydrogen flame reaches a very high temperature of about 2800 degrees Celsius. This high temperature is significant for various industrial applications.

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