Pre-AP Chemistry
Instructor: Mrs. Blakely
Name ___________________________________ Period _________ Due Date _____________
Laboratory Activity: Ammonia and Ammonium
Ammonia is a common gas (NH3) that has a sharp odor. Salts of ammonia have been
known since the 13th century. Ammonia was produced by the action of alkalis on sal-ammoniac.
Gaseous ammonia was isolated in 1774 by Priestly, Scheele identified the nitrogen content in
1777, and Berthollet identified its composition in 1785. Ammonia is a gas made from nitrogen
and hydrogen in the Haber Process that was patented in 1910. Most people are familiar with it as
a household cleaner, which is generally a 5-10% aqueous solution by weight. Household
ammonia is also considered to be a weak ammonium hydroxide solution. Ammonium salts can
be found as a variety of industrial and consumer products. Solutions of these salts react with
strong bases to produce ammonia, as example, in the following reaction:
NH4Cl (aq) + NaOH (aq)  NH3 (g) + H2O (l) + NaCl (aq)
Some ammonium salts undergo a natural decomposition in air to release ammonia gas.
Ammonia will react with moist neutral litmus paper, turning it blue, as an indication of the base
formed. This activity will allow you to study ammonia as a compound and the ammonium ion.
Materials- household ammonia, NH4Cl (s), NaOH (aq), test tubes with rack, test tube holder,
stoppers, burner, sparker, neutral litmus paper, 10 ml graduated cylinder, NH4NO3 (s),
(NH4)2CO3 (s), fertilizer, window cleaner.
Methods1. Fill a test tube 1/3 full with ammonia. Observe the odor and test with a moist litmus paper
holding it above the surface of the liquid in the test tube.
2. Gently heat the test tube in the burner, observe the odor again and test with a moist litmus
paper. Discard this solution in the sink.
3. Observe the odor of the ammonium chloride(s) sample provided. Test the solid by holding a
moist litmus paper above it.
4. Dissolve a small amount (about a gram) of ammonium chloride(s) in a test tube 1/3 full of
water (swirl or stopper).
5. Observe the odor, test with moist litmus. Add 3 ml of NaOH (aq), mix, gently heat, then
observe the odor, test with moist litmus again. Discard the products of the reaction in the sink.
6. Repeat steps 3, 4, and 5 individually using the (NH4)2CO3, NH4NO3, and the fertilizer in
place of the ammonium chloride.
7. Observe the sample of window cleaner. Test in anyway feasible to determine ammonia
content. Note what tests you used and the results.
Observations (60 pts) Note: No more than two words for odor or litmus. Litmus is only red
or blue. (ex. for odor- salty, musty, very pungent, mildly acidic; for litmus: red, dark blue,
instant blue)
1. NH3 (aq) sample-
odor- ________________________ litmus- _____________
2. NH3 (aq) sample with heat-
odor- ________________________ litmus- _____________
3. NH4Cl (s)over----
odor- ________________________ litmus- _____________
4. NH4Cl (aq)-
odor- ________________________ litmus- _____________
5. NH4Cl reaction-
odor- ________________________ litmus- _____________
6. (NH4)2CO3 (s)-
odor- ________________________ litmus- _____________
7. (NH4)2CO3 (aq)-
odor- ________________________ litmus- _____________
8. (NH4)2CO3 reaction-
odor- ________________________ litmus- _____________
9. NH4NO3 (s)-
odor- ________________________ litmus- _____________
10. NH4NO3 (aq)-
odor- ________________________ litmus- _____________
11. NH4NO3 reaction-
odor- ________________________ litmus- _____________
12. fertilizer (s)-
odor- ________________________ litmus- _____________
13. fertilizer (aq)-
odor- ________________________ litmus- _____________
14. fertilizer reaction-
odor- ________________________ litmus- _____________
15. window cleaner- _________________________________________________________
___________________________________________________________________________
Questions (40 pts)
1. Name two ways that ammonia is different from ammonium?
2. Why is fertilizer used as a sample in this lab?
3. Ammonia plays a very minor role in window cleaners. Explain its use.
4. Why is the heating of the test tube solutions done in this lab?
5. What are two basic safety precautions to be taken when using ammonia in the home or lab?