Question

The gas used in the welding and cutting of metal is:
A.Ethane
B.Ethene
C.Ethyne
D.Propene

Answer 1

Hint: In welding, two parts of a metal are joined together with the use of extreme heat or with some addition of metals or gases, which makes these two pieces joint together and become one. There are different methods for welding.

Complete step by step answer:
Heat is required to melt a metal at an accelerated rate to achieve a cut.
Ethyne is also known as acetylene which has a chemical formula, ${{C}_{2}}{{H}_{2}}$ . It is the simplest alkyne. It is unstable in its pure form and therefore, it is usually handed as a solution.
Ethyne is used for welding and cutting of metals. The welding process which uses ethyne is called as gas cutting or oxy – fuel cutting. In this method, materials are weld or cut at a very high temperature around $3500{}^\circ C$ . Among all the other gases we have observed that ethyne is able to produce the hottest flame. Therefore, ethyne plays a very important medium in the cutting of metals and welding. Ethyne is used in the fabrication of other metal parts in which accuracy is crucial.
Therefore, the correct option is (C) Ethyne.

Additional information:
As we have discussed, welding is a process used for joining metals by the use of high amounts of heat. It melts the parts together, fuses them and allows them to cool. Welding uses many energy sources for the cutting of metals. It uses gas flames, laser, ultrasound and electron beams.
It is very hazardous as it can cause electric shocks, burns, and inhalation of poisonous gas.

Note: High amount of temperature around $3500{}^\circ C$ , is required for the welding process.
Ethyne is a colourless gas which is used for the cutting of metals.
Acetylene is a colourless gas which is used as a fuel. It is unstable and therefore it is handled in a solution.