Practical work 5: identifying mineral fertilizers
Answers are for parents and teachers.
1
Which reagent separates NH₄NO₃ from (NH₄)₂SO₄, and why?
BaCl₂: white BaSO₄ with the sulfate, none with the nitrate.
2
How many mol of NH₃ are released when 2 mol NH₄Cl is warmed with NaOH?
2 mol
3
A white crystalline fertilizer gave no precipitate with AgNO₃ but released ammonia with warm NaOH. Which could it be (NH₄Cl, NH₄NO₃, KCl)?
NH₄NO₃
4
Calculate Mᵣ(NH₄Cl) (Aᵣ: N 14, H 1, Cl 35.5). Give the answer as a decimal.
53.5
5
Why can fertilizers never be identified by tasting?
Many are poisonous; in chemistry identification is by reactions.