Ammonia liberation from ammonium salts via base reaction

Steps:

• Ammonium nitrate dissociates in water to NH4+ and NO3- ions.
• Ammonia gas (NH3) is liberated when NH4+ reacts with a strong base like hydroxide on warming.
• Potassium hydroxide (KOH) provides OH- ions for this reaction.
• The equation is NH4NO3 + KOH → KNO3 + NH3↑ + H2O.

Why B is correct:

• KOH, a strong base, reacts with NH4+ to produce ammonia gas via acid-base neutralization, forming water and the soluble nitrate salt.

Why the others are wrong:

• A. Calcium nitrate is a neutral salt with no basic properties to react with NH4+.
• C. Sodium chloride is a neutral salt that does not affect the ammonium ion.
• D. Sulfuric acid is an acid that would form ammonium sulfate, not liberate NH3.

Final answer: B