Practical : 5

TITLE : Ammonia, Sulphuric Acid and Nitric Acid

Aim : To prepare ammonium salt fertilizer

Introduction : 1. Ammonium sulphate, chemical compound, (NH4)2SO4, a

colorless-to-gray, rhombohedral crystalline substance

that occurs in nature as the mineral mascagnite.

2. It is soluble in water and insoluble in alcohol or liquid

ammonia. It is prepared commercially by passing

ammonia, obtained from destructive distillation of coal,

into sulfuric acid and is used as a fertilizer, in preparing

other ammonium compounds, and for fireproofing.

3. Ammonia is manufactured in industry by the Haber

process. Nitrogen and hydrogen are mixed in the ratio

of 1: 3 volumes and passed over iron fillings (catalyst)

mixed with aluminium oxide (promoter) at 4500C –

5500C. The optimum pressure used in this process is

200 atmospheres.

4. Nitrogen is obtained from air by fractional distillation of

liquefied air.

5. Hydrogen is obtained from the reaction of steam with

charcoal or natural gas.

6. The use of low temperatures and high pressures is not

cost effective as the rate of production becomes slower,

even though the percentage production of ammonia

increases.

7. Thus the optimum temperature and pressure used here

are 4500C – 5500C and 200 atmosphere. About 15% of

NH3 is obtained in this way and the unreacted nitrogen

and hydrogen gases are recirculated through the

catalyst tower.

Materials / : Ammonia solution (2M), dilute sulphuric acid (1M), beaker,

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Apparatus glass rod, Bunsen burner, tripod stand, wire gauze, filter funnel

and filter

Procedure : 1. 30 cm³ of dilute sulphuric acid is poured into a beaker.

(Figure 1)

Figure 1

2. The ammonia solution is added little by little into the

beaker while stirring the solution. (Figure 2)

Figure 2

3. Did not add any ammonia solution when the solution

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smells amniotic.

4. The solution is heated until it become 1/3 of the original

volume.( Figure 3 and 4)

Figure 3 Figure 4

5. The solution is cooled in a mixture of ice and water.

(Figure 5) The salt crystals produced using the filter

funnel and filter paper.(Figure 6 and 7)

Figure 5

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Figure 6 Figure 7

Figure 8 : Preparation of ammonium salt fertilizer

Result :

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The white crystals formed are ammonium sulphate

Discussions :1. Write a balance equation to represents the formation of ammonium

sulphate in this experiment.

2 NH3 + H2 SO4 (NH4)2 SO4

2. How does the addition of ammonium sulphate affects the pH of the soil?

Untuk meneutralkan tanah atau mengurangkan keasidan tanah.

3. Beside fertilizers, ammonium sulphate is also used as an agriculture spray

adjuvant for water soluble pesticides. Explain the function of ammonium

sulphate in this area.

Ammonia digunakan sebagai bahan untuk menghasilkan racun serangga

perosak.

4. Name three examples of natural fertilizer which are used in farming.

a. Baja najis 5

b. Bahan bakar (kompos)

c. Baja organic

5. Name three examples of synthetic fertilizer which are used in agriculture.

a. Urea

b. Ammonium nitrat

c. Ammonium fosfat

6. Write chemical equations to represent the formation of:

a) ammonium phosphate

NH3 + H3 PO4 (NH4)2 PO4

b) ammonium nirate

NH3 + HNO3 NH4 NO3

c) urea

CO + 2NH3 CO (NH2)2 H2O

7. .Calculate the percentage of nitrogen in 1 mole of the fertilizers.

[Relative atomic mass: H,1; C,12; N,14; O,16; P,31; S,32 ]

Relative atomic Mass of nitrogen

% N = ---------------------------------------------------- X 100

Relative Molecular mass of fertiliser

a) ammonium phosphate

b) ammonium nirate

c) urea

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8. Which of the above fertilizer is the most suitable for the growth of plants?

Explains your answer.

Baja ammonium, ialah baja bernitrogen yang dapat membekalkan unsur

nitrogen untuk tumbuhan. Tidak balas peneutralan yang berlaku antara

larutan ammonia, NH3 (ak), dengan larutan asid menghasilkan garam

ammonium, NH4, yang dapat digunakan sebagai baja.

Conclusion :The white crystals formed are ammonium sulphate.

References :

Chan See Leong,Chong Kum Ying, Choo Yan Tong, Low Swee Neo,(2009).Fokus Ace PMR, Science.Selangor,Pelangi Sdn.Bhd.

Chong Kum Ying & Chang See Leong. (2002). Fokus Ungu SPM Sains. Bangi,

Selangor : Penerbitan Pelangi Sdn. Bhd.

Mah Chee Wai & Lim Swee Kim. (2011). Nexus SPM Chemistry. Petaling Jaya:

Sasbadi Sdn. Bhd.

Tan Yin Toon,Loh Wai Leng,Tan On Tin,(2009) Success Chemistry SPM.Oxford

Fajar.Shah Alam ,Selangor

Toh Kim Kau,(2009). NEXUS VISTA SPM, CEMISTRY Selangor, Sasbadi Sdn.Bhd.

S.H. Chan.(2011). Kimia SPM; Kuasai Melalui Diagram. Selangor: SAP

Publications.

Suhaila Ahmad & Doris Siaw Hie Kiew. (2011). Memory Mastery Through Visual

Maps & Diagrams Chemistry SPM. Selangor: PNI Neuron(M) Sdn. Bhd.

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Vijaya Viswanathan & Catherine Lee. (2012). Suplemen SPM

Chemistry .Selangor: Marshall Cavendish (Malaysia) Sdn. Bhd.

Vijaya Viswanthan, Catherine Lee.(2009) New vision 3G SPM: Chemistry

Marshall Cavendish . Shah Alam .Selangor

http://www.mse.vt.edu/faculty/staley/2034/2034module.4.pdf

http://www.newagepublishers.com./sample.chapter/000627.pdf

http://www.freepatentsonline.com/6344066.html

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