Question

Why are arc sources often blanketed with a stream of inert gas?

Short answer

Arc sources are often blanketed with a stream of inert gas so asto neglect some atmospheric gases such as nitrogen.

Step-by-step solution

Step 1. Given information

State reason for the arc sources often blanketed with a stream of inert gas.

Step 2. Arc sources

Arc sources are often blanketed with a stream of inert gas so asto neglect some atmospheric gases such as nitrogen. This is because these gasesform cyanogens compounds when treated with heated graphite. Inert gases used can be either carbon dioxide or argon.

Step 3. Graphite Electrodes

Arc sources essentially comprise graphite electrodes. When there is a use of inert gas in the arc source, then the gas called nitrogen is excluded due to avoid any probability of formation of cyanogen compound.