Solution:Concept- In order to solve the given problem, we must first comprehend the fundamental chemical name of each molecule. Then, with the use of a chemical equation, we can examine the chemical reaction that each compound goes through during the heating process. We will also determine which of the provided compounds does not give out oxygen when heated on the basis of the chemical reaction.
Chromium oxide and water are produced when ammonium dichromate is heated, and nitrogen gas is also released along with it. However, there is no emission of oxygen gas.
All of the compounds in the list of choices are oxygen-rich, but only ammonium dichromate is not; as a result, each of the other compounds releases oxygen when heated, whereas ammonium dichromate releases nitrogen.
When we heat ammonium dichromate it does not evolve oxygen, even release nitrogen dioxide and water.
Hence, the correct answer is option 4.