ammonia

Selina Concise Chemistry Class 10 ICSE Solutions Study of Compounds – Study of Compounds – Ammonia

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Selina Concise Chemistry Class 10 ICSE Solutions Study of Compounds – Study of Compounds – Ammonia

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Selina ICSE Solutions for Class 10 Chemistry Chapter 9 Study of Compounds – Ammonia

Exercise Intext 1

Solution 1.

selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-ina-1

Solution 2.

The different forms of ammonia:

Gaseous ammonia(dry ammonia gas)
Liquid ammonia
Liquor ammonia fortis
Laboratory bench reagent

Solution 3.

Formula of liquid ammonia is: NH3.
Liquid ammonia is liquefied ammonia and is basic in nature. It dissolves in water to give ammonium hydroxide which ionizes to give hydroxyl ions.
selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-ina-3

Solution 4.

selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-ina-4

Solution 5.

(a) Lab preparation of ammonia:
2NH4Cl + Ca(OH)2 → CaCl2 +2H2O +2NH3
(b) The ammonia gas is dried by passing through a drying tower containing lumps of quicklime (CaO).
(c) Ammonia is highly soluble in water and therefore it cannot be collected over water.

Solution 6.

The drying agent used is CaO in case of ammonia.
Other drying agents like P2O5 and CaCl2 are not used. As ammonia being basic reacts with them.
6NH3 + P2O5 + 3H2O → 2(NH4)3PO4
CaCl2 +4NH3 → CaCl2.4NH3

Solution 7.

The substance A is Ammonium chloride and ‘B’ is Ammonia.
Reaction:
2NH4Cl + Ca(OH)2 → CaCl2 + 2H2O + 2NH3

Solution 8.

selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-ina-8

Solution 9.

(a) Ammonium compounds being highly soluble in water do not occur as minerals.
(b) Ammonium nitrate is not used in the preparation of ammonia as it is explosive in nature and it decomposes forming nitrous oxide and water vapours.
(c) Conc. H2SO4 is not used to dry ammonia, as ammonia being basic reacts with them.
2NH3 + H2SO4 → (NH4)2SO4

Solution 10.

Preparation of Aqueous Ammonia: An aqueous solution of ammonia is prepared by dissolving ammonia in water. The rate of dissolution of ammonia in water is very high; therefore, back suction of water is possible. To avoid this, a funnel is attached to the outer end of the delivery tube with rubber tubing.

Procedure: Water is taken in a container and only a small portion of the mouth of funnel is dipped in water.

As ammonia dissolves in water at a higher rate than its production in the flask, the pressure in the funnel above water level decreases for a moment and water rushes into the funnel. As a result, the rim of the funnel loses its contact with water. Since, ammonia produced pushes the water down, the funnel comes in contact with water again. In this way, ammonia dissolves in water without back suction of water.

selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-ina-10

Exercise 1

Solution 1.

Physical properties of ammonia are:

Color: Colourless
Odour: Strong, Pungent chocking smell
Taste: Slightly bitter (alkaline ) taste
Physiological action: Non-Poisonous
Density: V.D = 8.5 Lighter than air
Nature: Alkaline
Liquefaction: easily liquefied at 10oC by compressing it at 6 atm. Pressure
Boiling Point: Liquid ammonia boils at -33.5oC
Freezing Point: Solid NH3 melts at -77.7oC
Solubility: Highly soluble in water, 1vol of water dissolves about 702 vols. of ammonia at 20oC and 1 atm. pressure.
Reaction:
2NH4Cl + Ca(OH)2 → CaCl2 + 2H2 + 2NH3

selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-1

Solution 2.

Ammonia is less dense than air. By Fountain Experiment we demonstrate the high solubility of ammonia gas in water.
Balanced equation for the reaction between ammonia and sulphuric acid is:
2NH3 + H2SO4 → (NH4)2SO4

Solution 3.

(a) Ammonia is basic in nature.
(b) Copper oxide because CuO is less reactive can be reduced by C, CO or by hydrogen whereas Al2O3, Na2O, MgO are reduced by electrolysis.

Solution 4.

(a) The formula of the compound is Mg3N2.
(b) Balanced equation :
Mg3N2 + 6 H2O → 3Mg(OH)2 + 2 NH3
(c) Ammonia is a reducing agent and reduces less active metal oxide to its respective metal.

Solution 5.

Reducing property.

Solution 6.

When a piece of moist red litmus paper is placed in a gas jar of ammonia it turns blue.

Solution 7.

(a) The gas is ammonia.
(b) The formula is NH3.
(c) Uses of ammonia:

  1. It is used in the industrial preparation of nitric acid by Ostwald process.
  2. It is used in the manufacture of fertilizers such as ammonium sulphate, ammonium nitrate, ammonium phosphate.
  3. It is used in the manufacture sodium carbonate by Solvay process.
    NaCl + NH3 + CO2 + H2O → NaHCO3 + NH4Cl

Solution 8.

Equation:
CuSO4 + 2NH4OH → Cu(OH)2 ↓ + NH4]2SO4
pale blue

Ammonia solution in water gives a blue precipitate when it combines with a solution of copper salt.

The pale blue precipitate of copper hydroxide dissolves in excess of ammonium hydroxide forming tetraamine copper[II] sulphate, an azure blue(deep blue)soluble complex salt.
Cu(OH)2 +(NH4)2SO4 +2NH4OH → [Cu(NH3)4]SO4 + 4H2O

Solution 9.

selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-9

Solution 10.

(a) Liquid ammonia takes a lot of energy to vaporize .This heat is taken from the surrounding bodies which are consequently cooled down. Thus it is used as a refrigerant in ice plant.
(b) Ammonia emulsifies or dissolves fats, grease so it is used to remove grease from woolen clothes.
(c) Aqueous solution of ammonia gives pungent smell because of the presence of ammonia.
(d) Aqueous ammonia when dissolved in water breaks into ions which help in the conductance of electricity.
selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-10

Solution 11.

(a) AlN + 3H2O → Al(OH)3 +NH3
(b) 2NH3 + 3PbO → 3Pb + 3H2O + N2
(c) 8NH3 +3Cl2 → N2 + 6NH4Cl
(d) 2NH3 + CO2 → NH2CONH2 + H2O
(i) Ammonia act as reducing agent is explained by equation (c).
(ii) Urea the nitrogenous fertilizer is prepared from equation (d).

Solution 12.

(a) A Dirty green precipitate of Fe(OH)2 is obtained when ammonium hydroxide is added to ferrous sulphate.
(b) Liquid ammonia is liquefied ammonia.
(c) Finely divided Iron is used in Haber process.
(d) Quicklime is a drying agent for NH3.
(e) Ammonium salts when heated with caustic alkali.

Solution 13.

(a) Dirty green ppt. of Ferrous hydroxide is formed which is insoluble in excess of NH4OH.
FeSO4 + 2NH4OH → [NH4]2SO4 + Fe(OH)2

(b) Reddish brown ppt. of ferric hydroxide is formed which is insoluble in ammonium hydroxide.
FeCl3 + 3NH4OH → 3NH4Cl + Fe(OH)3

(c) White ppt. of lead hydroxide is formed which is insoluble in NH4OH.
Pb(NO3)2 + 2NH4OH → 2NH4NO3 + Pb(OH)2

(d) White gelatinous ppt. of Zinc hydroxide is formed which is soluble in NH4OH.
Zn(NO3)2 + 2NH4OH → 2NH4NO3 + Zn(OH)2

Solution 14.

When correct amount of ammonium hydroxide is added drop wise to solutions of the metallic salts, ppts. (coloured generally) are formed. They help us to identify their metal ions.
Two equations:
FeSO4 +2NH4OH → (NH4)2SO4 + Fe (OH)2
(Green) (Dirty green)
shows the presence of Fe+2 ion.
FeCl3 + 3NH4OH → 3NH4Cl + Fe (OH)3
(Brown) (Reddish brown)
shows the presence of Fe+3 ion.

Solution 15.


NH4Cl on strong heating sublimes to form dense white fumes which condense to white powdery mass on cooler parts of the tube whereas no white fumes on heating NaCl.

(b) When ammonium hydroxide is added drop wise to solution to be tested.
Ferrous salt gives dirty green ppt.
Ferric salt gives reddish brown ppt of their hydroxides.

(c) (NH4)2SO4 on warming with NaOH sol. gives NH3 gas. Sodium sulphate does not liberate NH3 gas.

Solution 16.

selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-16

Solution 17.

(a) In the presence of Platinum at 800oC, ammonia reacts with oxygen to give nitric oxide and water vapour.
Procedure:
Pass dry ammonia gas and oxygen gas through inlets over heated platinum placed in the combustion tube, which in the heated state emits reddish glow.

selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-17
Observation:
Reddish brown vapours of nitrogen dioxide are seen in the flask due to the oxidation of nitric oxide.
The platinum continues to glow even after the heating is discontinued since the catalytic oxidation of ammonia is exothermic.

(b) Two reactions to show reducing property of ammonia are:
8NH3 +3Cl2 → N2 + 6NH4Cl
2NH3 +3CuO → 3Cu + 3H2O +N2

Solution 18.

(i) Neutralization
NH3 + HCl → NH4Cl

(ii) Thermal dissociation
NH4Cl → NH3 + HCl

(iii) Ammonia
NH4Cl + NaOH → NH3 + NaCl + H2O

Solution 19.

(a) Ammonia
(b) Hydrogen chloride and chlorine gas.

(c) (i) Ammonium chloride
(i) Ammonium nitrate
(ii) Ammonium carbonate

(d) Acidic gas: HCl
Basic gas: Ammonia
Neutral gas: NH4Cl

(e) Silver chloride
(f) Nitrogen
(g) Magnesium nitride
(h) Lead oxide
(i) Ammonium chloride

Solution 20.

CuSO4 + 2NH4OH → (NH4)2SO4 + Cu(OH)2 [Pale blue]
The cation present in solution B is Copper (Cu+2).
The colour of solution B is Blue.
The pale blue precipitate of copper hydroxide dissolves in excess of ammonium hydroxide forming tetraamine copper[II] sulphate, an azure blue(deep blue) soluble complex salt.
Cu(OH)2 + (NH4)2SO4 +2NH4OH →  [Cu(NH3)4]SO4 + 4H2O

Solution 21.

Three ways in which ammonia gas can be identified is:

  1. It has a sharp characteristic odour.
  2. When a glass rod dipped in HCl is brought in contact with the gas white colour fumes of ammonium chloride are formed.
  3. It turns moist red litmus blue, moist turmeric paper brown and phenolphthalein solution pink.

Solution 22.

(a) Mg3N2 + 6H2O 3Mg(OH)2 + 2NH3
(b) 2NH3 + 3CuO 3Cu + 3H2O + N2
Ammonia acts as a reducing agent. It reduces metallic oxide to give metals, water vapour and nitrogen.
(c) 8NH3 +3Cl2 N2 + 6NH4Cl
(d) 4 NH3 +5O2 6H2O + 4NO +Heat
Ostwald process starts with the catalytic oxidation of ammonia to manufacture nitric acid in the presence of catalyst platinum.

Solution 23.

As the ‘A’ turns red litmus blue it is a base. Now the gas ‘A’ combines with ‘B’ in presence of Catalyst to give colourless gas Nitrogen monoxide. It reacts with oxygen to give brown gas which is Nitrogen dioxide.
A= NH3
B= O2
C=NO
D=NO2

selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-23

Solution 24.

selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-24

Solution 25.

(a) The main refrigerants used are Freon chlorofluorocarbons (CFC). They deplete ozone layer. The chlorofluorocarbons are decomposed by ultraviolet rays to highly reactive chlorine which is produced in the atomic form.selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-25
This causes depletion of ozone layer and chlorine monoxide so formed reacts with atomic oxygen and produces more chlorine free radicals.
ClO + O → Cl + O2
Again this free radical destroys ozone and the process continues thereby giving rise to ozone depletion.
(b) Liquid ammonia can be used as a refrigerant, as an alternative for chlorofluorocarbons.
(c) Advantages of ammonia as refrigerant:

  1. Ammonia is environmentally compatible. It does not deplete ozone layer and does not contribute towards global warming.
  2. It has superior thermodynamic qualities as a result ammonia refrigeration systems use less electricity.

Ammonia has a recognizable odour and so leaks are not likely to escape.

Solution 26.

Disadvantages of ammonia as a refrigerant are as follows:

  1. It is not compatible with copper, so it cannot be used in any system with copper pipes.
  2. It is poisonous in high concentration although it is easily detectable due to its peculiar smell and since it is less dense than air it goes up in the atmosphere not affecting the life too much on earth.

Solution 27.

(a) Explosive: ammonium nitrate
(b) Medicine: ammonium carbonate
(c) Fertilizers: ammonium sulphate
(d) Laboratory reagent: ammonia solution

Solution 28.

(a) Dry air free from carbon dioxide and dry ammonia from Habers process.
(b) The catalyst used in the process is Platinum.
(c) The oxidizing agent used in the process is oxygen.
(d) Ratio of ammonia and air is 1:10.
(e) Quartz is acid resistant and when packed in layers help in dissolving nitrogen dioxide uniformly in water.

Solution 29.

selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-29

Solution 30.

selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-30

Solution 1 (2003).

(a) Mg3N2 +6H2O → 3Mg(OH)2 + 2NH3
(b) Ammonia gas is collected in inverted gas jars by the downward displacement of air.
(c) Ammonia is not collected over water because it is highly soluble in water.
(d) Quicklime is used as a drying agent for ammonia.

Solution 1 (2004).

selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-1-2004

Solution 1 (2005).

(a) It is the basic nature of ammonia molecule.
(b) Hydroxyl ion (NH3 + H2O → NH4+ + OH–)
(c) The red litmus paper turns blue in the solution.

Solution 1 (2006).

Pb(NO3)2+ NH4OH → 2NH4NO3+Pb(OH)2
The chalky white ppt. of lead hydroxide is formed.

Solution 1 (2007).

(a) HCl gas is more dense [V.D.=18.25,V.D. of ammonia =8.5] and it is collected by the upward displacement of air.
(b) NH3 + HCl → NH4Cl

Solution 2 (2005).

selina-icse-solutions-class-10-chemistry-study-compounds-study-compounds-ammonia-2-2005

Solution 2 (2007).

Balanced equation:

(a) 2NH3 + 3CuO → 3Cu + 3H2O + N2
(b) 2NH3 + 3Cl2 → N2 + 6HCl

Solution 2 (2008).

Magnesium Nitride

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Uses of ammonia in our daily life

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Uses of ammonia in our daily life

Uses of ammonia:

  1. Ammonia is produced industrially as an intermediate compound and as raw material for many other chemical processes.
  2. The main uses of ammonia are as follows:
    (a) To manufacture nitrogenous fertilisers needed for plant growth
    (b) As raw material for the manufacture of nitric acid
    (c) As cooling agent in refrigerators
    (d) To produce ammonium chloride used as electrolyte in dry cells
    (e) To prevent coagulation of latex
    (f) To make synthetic fibres such as nylon
    (g) As smelling salts to revive people who have fainted
    (h) Making of explosives
    Uses of ammonia in our daily life 1
  3. The nitrogenous fertilisers are actually ammonium salts obtained from neutralisation of ammonia with different acids. These fertilisers include:
    (a) Ammonium phosphate
    The reaction of ammonia with phosphoric acid produces ammonium phosphate.
    2NH3(aq) + H3PO4(aq) → (NH4)2HPO4(aq)
    Ammonium phosphate is a good fertiliser as it provides two important nutrients, nitrogen and phosphorus.
    (b) Ammonium nitrate
    Ammonia reacts with nitric acid to produce ammonium nitrate.
    NH3(aq) + HNO3(aq) → NH4NO3(aq)
    (c) Ammonium sulphate
    Ammonia reacts with sulphuric acid to produce ammonium sulphate.
    2NH3(aq) + H2SO4(aq) → (NH4)2SO4(aq)
    (d) Urea
    Ammonia reacts with carbon dioxide at 200°C and atmospheric pressure of 200 to produce urea.
    2NH3(g) + CO2(g) → CO(NH2)2(s) + H2O(l)
    Urea has the highest percentage of nitrogen and is very suitable for plant growth.
  4. Ammonia is used to make nitric-acid through Ostwald process. This process involves three stages.
    (a) Ammonia is oxidised to nitrogen monoxide in the presence of platinum as the catalyst.
    4NH3(g) + 5O2(g) → 4NO(g) + 6H2O(l)
    (b) Nitrogen monoxide is further oxidised to nitrogen dioxide.
    2NO(g) + O2(g) → 2NO2(g)
    (c) Nitrogen dioxide and oxygen dissolve in water to form nitric acid.
    4NO2(g) + O2(g) + 2H2O(1) → 4HNO3(aq)
  5. Liquid ammonia is used as cooling agent in refrigerators because ammonia is highly compressible and has a high heat capacity.
  6. Ammonia can neutralise the acid produced by bacteria in the latex, thus preventing latex from coagulating and can be exported in the liquid form.
  7. Ammonia reacts with hydrochloric acid to form ammonium chloride. Ammonium chloride is used as electrolyte in dry cells.
    NH3(aq) + HCl(aq) → NH4Cl(aq)
  8. Ammonia reacts with nitric acid to form ammonium nitrate which is used as explosive. Nitric acid can be used to make explosives such as TNT.

People also ask

Ammonium fertilisers

  1. Nitrogen is used by plant to make protein. Protein is important for the growth of plant. Other nutrients needed by plants include phosphorus, potassium, calcium and magnesium.
  2. Nitrogenous compounds are removed from the soil by plants; some are replaced naturally by bacteria. To restore the balance, nitrogenous fertilisers are added to the soil.
  3. Nitrogenous fertilisers include ammonium fertilisers which contain ammonium ions.
  4. In the soil, the ammonium ions are converted to nitrate ions by bacteria. This is because nitrogen can only be absorbed by plants in the form of soluble nitrate ions.
  5. Examples of ammonium fertilisers are:
    (a) Ammonium nitrate, NH4NO3
    (b) Ammonium sulphate, (NH4)2SO4
    (c) Ammonium phosphate, (NH4)3PO4
    (d) Urea, CO(NH2)2
  6. The effectiveness of ammonium fertilisers is determined by the percentage of nitrogen by mass in them.
  7. The fertiliser with a higher percentage of nitrogen is more effective for growth than those fertilisers with a low percentage of nitrogen.
  8. The percentage of nitrogen by mass can be calculated from the formulae of the fertilisers using the following formula.
    Uses of ammonia in our daily life 2

Example: The following are four fertilisers.
Ammonium nitrate, NH4N03
Ammonium sulphate, (NH4)2S04
Ammonium phosphate, (NH4)3P04 . Urea, CO(NH2)2
Which fertiliser is most suitable for the growth of plants? [Relative atomic mass: H, 1; C, 12; N, 14; O, 16; P, 31; S, 32]
Solution:
Uses of ammonia in our daily life 3
Uses of ammonia in our daily life 4

What are the physical properties of ammonia?

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What are the physical properties of ammonia?

  1. Ammonia is a covalent compound with the following physical properties:
    What are the physical properties of ammonia 1
  2. Ammonia is very soluble in water, but it ionises partially in water to form a weak alkali. A 0.1 mol dm-3 ammonia solution has a pH of about 10.
    What are the physical properties of ammonia 2
  3. Ammonia being alkaline can undergo neutralisation with acids to form ammonium salts.
    Ammonia + Acid → Ammonium salt
    Examples:
    (a) Ammonia neutralises sulphuric acid to form ammonium sulphate.
    2NH3(aq) + H2SO4(aq) → (NH4)2SO4(aq)
    (b) Ammonia gas reacts with hydrogen chloride gas to form dense white fumes of ammonium chloride. This is used as a test for detecting ammonia gas.
    NH3(g) + HCl(g) → NH4Cl(s)
  4. Ammonia solution can react with solutions of some metal ions (except Na+ ion, K+ ion and Ca2+ ion) to produce precipitate of metal hydroxide.
    Mn+(aq) + nOH–(aq) → M(OH)n(s)
    Examples:
    (a) Ammonia reacts with copper ions to produce a blue precipitate, copper(II) hydroxide.
    What are the physical properties of ammonia 3
    Copper(II) hydroxide dissolves in excess ammonia solution to form a dark blue solution.
    (b) Ammonia reacts with zinc ions to produce a white precipitate, zinc hydroxide.
    What are the physical properties of ammonia 4
    Zinc hydroxide dissolves in excess ammonia solution to form a colourless solution.
    (c) Ammonia reacts with iron(III) ions to produce a brown precipitate, iron(III) hydroxide.
    What are the physical properties of ammonia 5
    (d) Ammonia reacts with magnesium ions to produce a white precipitate, magnesium hydroxide.
    What are the physical properties of ammonia 6
  5. Ammonia does not burn in air, but in the presence of platinum catalyst in oxygen, ammonia can burn to produce nitrogen dioxide.
    4NH3(g) + 5O2(g) → 4NO(g) + 6H2O(l)

People also ask

Laboratory preparation of ammonia gas experiment

Aim: To investigate the properties of ammonia.
Materials: 0.1 mol dm-3 ammonia solution, 0.1 mol dm-3 sodium hydroxide solution, ammonium chloride, calcium hydroxide, concentrated hydrochloric acid, soda-lime, distilled water, red litmus paper, pH paper.
Apparatus: Test tubes, beaker, U-tube, Bunsen burner, glass rod, delivery tube, stoppers.
Procedure:

Safety Measures

  • Do not inhale ammonia gas.
  • Concentrated hydrochloric acid is corrosive.
  • Carry out this activity in a fume chamber.

A. Preparation of ammonia gas
What are the physical properties of ammonia 7

  1. One spatula of ammonium chloride is mixed with one spatula of calcium hydroxide.
  2. The apparatus as shown in Figure is set up.
  3. The mixture is heated strongly.
  4. The ammonia gas produced is collected in a few test tubes. The test tubes containing ammonia gas must be closed with stoppers.

B. Alkalinity of ammonia

  1. 5 cm3 of 0.1 mol dm-3 ammonia solution and 5 cm3 of 0.1 mol dm-3 sodium hydroxide solution are poured into two separate test tubes.
  2. A piece of pH paper is dipped into the solution in each test tube.
  3. The pH values of both solutions are recorded.

C. Colour, physical state, smell and solubility of ammonia
What are the physical properties of ammonia 8

  1. The colour and physical state of ammonia are observed.
  2. The stopper of a test tube containing ammonia gas is removed and the smell of the gas is identified.
  3. A test tube containing ammonia gas is inverted into a beaker of water.
  4. All observations are recorded.

D. Density of ammonia
What are the physical properties of ammonia 9

  1. A test tube containing ammonia gas is held upright and another test tube containing ammonia gas is held upside down.
  2. The stoppers of the two test tubes are removed.
  3. After 20 seconds, a piece of moist red litmus paper is put at the mouth of each test tube as shown in Figure.
  4. The colour of the red litmus paper is recorded.

E. Chemical property of ammonia

  1. One end of a glass rod is dipped into concentrated hydrochloric acid.
  2. The glass rod is then put on top of a test tube of ammonia gas.
  3. Any change taking place is observed.

Observations:

SectionObservationInference
BpH of ammonia solution is 10.
pH of sodium hydroxide solution is 14.		Ammonia is a weak alkali.
Sodium hydroxide is a strong alkali.
CColourless gas
Pungent smell
Water rushes up and fills up the whole test tube.		Ammonia is a colourless gas with a pungent smell.
Ammonia is very soluble in water.
DMoist red litmus paper on top of the upright test tube does not change colour.
Moist red litmus paper under the inverted test tube turns blue.		Ammonia gas has escaped from the upright test tube and thus is slightly less dense than air.
EDense white fumes are formed.Ammonia reacts with hydrogen chloride gas to form ammonium chloride.

Discussion:

  1. Ammonia is a weak alkali and has a pH of 10.
  2. Ammonia is a colourless gas with a pungent smell.
  3. Ammonia is very soluble in water, ionises partially in water to form ammonium ions and hydroxide ions.
    What are the physical properties of ammonia 10
  4. Ammonia is slightly less dense than air.
  5. Ammonia reacts with hydrogen chloride gas to form ammonium chloride.
    NH3(g) + HCl(g) → NH4Cl(S)

Conclusion:
Ammonia is an alkaline, colourless gas with a pungent smell. It is very soluble in water and is less dense than air. It reacts with hydrogen chloride gas to form dense white fumes of ammonium chloride.