AMMONIAPrepared by: Faiz Abdullah

Do you know the chemical formula of ammonia?

NH3

NH4

NH4+

NO2

THIS ISAN AMMONIUMION

Properties of ammonia

Appearance

Smell

pHReactions

Preparation

At room temperature and pressure,

Ammonia is a colorless gas

Ammonia has a strong smell

Do you still remember??

Acid Base Salt

NH3

Ammonia is a

weak base!

Since NH3 is a base…

It is an alkali, because it can be dissolved in water

It turns damp litmus paper:RED BLUE

It turns a universal indicator blue showing a pH of 13

ReactionsLike any alkali, it reacts with AQ metal ions to give precipitates of metal hydroxides

Fe3+ (aq) + 3OH- Fe(OH)3 (s)

ANY alkali when dissolved in water produces OH-

How do you get AMMONIA?1. Ammonium salts react with STRONG alkali

NH4Cl + NaOH NH3 + NaCl + H2O

2. Nitrate ions are reduced by sodium hydroxide (aq) and aluminum metal

NO3- NH3

How do you get AMMONIA?

3. Haber Process

Haber ProcessNitrogen and Hydrogen GASES are reacted together to produce ammonia in a REVERSIBLE REACTION

N2(g) + 3H2(g) <-> 2NH3(g)

Nitrogen is obtained from air!

Hydrogen is obtained from cracking of petroleum fractions

Iron catalyst is being used to speed up reaction

Uses of AmmoniaUsually, ammonia is used to manufacture

NITROGEN FERTILIZERS

E.g.

NH3NO3

(NH4)2SO4 Ammonium sulphate

Ammonium Nitrate

Calculate the percentage of nitrogen in a fertilizer

Fertilizer (NH4)2SO4

% nitrogen =

Relative atomic mass of:H = 1N = 14O= 16S= 32

Sum of R.M.M of formula x100Sum of R.A.M. nitrogen in formula

132X 100

= 21.2 %

= (2 x 14)

End, now some questions…

MCQ

1. What is the source of the hydrogen used to manufacture ammonia in the Haber Process?

A. air

B. Haematite

C. Petroleum

D. Water

2. Which statement is true regarding the reaction in the Haber Process?

A. It is an exothermic reaction

B. The reaction produces an aqueous solution of ammonia

C. A platinum catalyst is used to speed up the reaction

D. The reaction is reversible

3. A high temperature is used in the Haber Process. Why?

A. To increase the percentage of ammonia

B. To increase the speed of reaction

C. To provide an activation energy for the reaction

D. To ensure the reaction goes completion

4. Is the reaction exothermic or endothermic for Haber Process?

A. Exothermic

B. Endothermic

C. Both

D. Stop asking me please!

5. Is the forward reaction exothermic or endothermic for Haber Process?

A. Exothermic

B. Endothermic

C. Both

D. Whatever, any answer I give is wrong anyway

6. The main use of ammonia is the manufacture of…

A. Paints

B. Nitric Acid

C. Obviously, agricultural fertilizers

D. Window cleaner

7. Ammonia gas is produced when ammonium salts react with..

A. Strong alkalis

B. Strong Acids

C. metals

D. Carbonates

8. Which fertilizer contains the greatest percentage by mass of nitrogen?

A. Ca(NO3)2

B. CO(NH2)2

C. NaNO3

D. NH4NO3

9. Which compound will eliminate acid in the soil but does not react with ammonium fertilizers?

A. Calcium carbonate

B. Calcium hydroxide

C. Calcium nitrate

D. Calcium oxide

Now, do the structured questions