Question

The ------------------ flame is used for the cutting and welding metals.

Answer 1

Uses of Hydrogen:

For cutting and welding metals: When a mixture of Hydrogen$\left({\mathrm{H}}_2\right)$ and Oxygen$\left({\mathrm{O}}_2\right)$ is burnt, it gives a very hot flame (of about 2800 ^oc).

• This flame is known as Oxy-hydrogen flame and is used for cutting and welding metals.

Hence, The Oxy-hydrogen flame is used for the cutting and welding metals.