Q. Warming Ammonium chloride with sodium hydrochloride in a test tube is an example of:
Answer: Open system
Notes: When heated, ammonium chloride decomposes into ammonia and hydrogen chloride. The thermal decomposition of ammonium chloride is a reversible chemical change. On heating above 340°C, it decomposes to form two gases such as ammonia and hydrogen chloride. On cooling, the reaction is reversed and solid ammonium chloride is formed. The reaction is an example of an open system in which exchange of mass and energy takes place with the surroundings.

• NH4Cl(s) <=> NH3(g) + HCl(g)

This question is part of 40000+ General Studies MCQ Series Course on GKToday Android app. Question Number: 71 in Chemistry-11-Chemical Reactions in above course in App.