How do ants identify a dead ant?

Ants are social like human being. They live in a colony and all of them are assigned to different works.

But today's question is how the ants identify a dead ant?

When an ant dies, a chemical named Oleic Acid emits from its body. For ants the smell of this acid is similar to death. When they smell this, they at once can identity the dead one and dispel it from the society.

Now another important thing is If this acid is sprayed on a living ant, the whole colony take it as dead. And in spite of being alive, it's dispelled.