Uses of ionic compound and covalent compound in daily life

CHEMISTRY FORM 4 KSSM
CHAPTER 5 : CHEMICAL BONDS
(Uses of ionic compound and covalent compound in daily life)

1. INDUSTRIAL SECTOR
2. AGRICULTURAL SECTOR
3. MEDICAL SECTOR
4. DOMESTIC USE

1. CHAPTER 5
CHEMICAL BONDS

2. 5.7.1Compare the properties of ionic and
covalent compounds through experiment.
List properties of ionic compounds.
List properties of covalent compounds.
Explain differences in the electrical conductivity of ionic and covalent
compounds.
Describe differences in the melting and boiling points of ionic and covalent
compounds.
Compare and contrast the solubility of ionic and covalent compound.
5.7 Properties of Ionic Compounds and
Covalent Compounds

3. Ionic Compound Covalent Compound
Exists as solids at room temperature. May exists as solids, liquids or gases.
Have highmelting and boiling points Have low meltingand boiling points.
Conduct electricity in aqueous solution or moltenstate. Do not conductelectricity.
Usually dissolve in water. Usually do not dissolve in water.
Usually do not dissolvein organic solvent. Usually dissolve in organic solvent.
Properties of Ionic and Covalent Compounds
1.Aqueous state : The substance is dissolved in water.
2.Molten state : The substance becomes ‘liquid form’ by heating
3.Organic solvents : Carbon-based substances capable of dissolving one or more other substances. Example :
Benzen, Acetone, Acetic Acid, Carbon Tetrachloride, Chloroform

4. EXPERIMENT 5.1
Aim: To study the difference in properties between ionic compounds and covalent
compounds.
Problemstatement: What are the difference in properties between ionic compounds
and covalent compounds?
Materials: Solid lead(Il) bromide, PbBr
2, naphthalene, C
10H
8, magnesium chloride,
MgCl
2, cyclohexane, C
6H
12and distilled water
Apparatus: Test tubes, spatula, evaporating dish, Bunsen burner, pipe clay triangle,
wire gauze, beaker, 10 cm
3
measuring cylinder, tripod stand, battery, switch, light bulb
and carbon electrodes

5. A.Electrical conductivity of compounds
Hypothesis : Ionic compounds can conduct electricity in molten state but not in
solid state while covalent compounds cannot conduct electricity in both states.
Variables :
a)Manipulated : Type of compound
b)Responding : Electrical conductivity
c)Fixed : Carbon electrode
Safety Precautions :
1.Naphthalene, C
10H
8, is a flammable substance
2.Bromine gas, Br2 produced during the heating of lead(II) bromide, PbBr
2is
poisonous

6. Procedure :
1.Put lead(II) bromide, PbBr
2powder into the crucible until half full.
2.Set up the apparatus as shown in Figure 5.21.
3.Switch on the circuit and observe whether the bulb light up.
4.Switch off and heat the lead(II) bromide, PbBr
2powder until all solids have melted.
5.Switch on once again and observe whether the bulb lights up.
6.Repeat steps 1 to 5 using naphthalene, C
10H
8powder.
7.Record your observation on the condition of the bulb in Table 5.1.

7. Results :
Compound Physical state Condition of thebulb
Lead(II)bromide, PbBr
2
Solid The bulb did not glow.
Molten The bulb glow brightly
Naphthalene, C
10H
8
Solid The bulb did not glow.
Molten The bulb did not glow.

8. B. Solubility of compounds in water and in organic solvent.
Hypothesis : Ionic compound dissolves in water but not in organic solvent whereas
covalent compound dissolves in organic solvent but not in water.
Variables :
a)Manipulated : Type of compound
b)Responding : Solubility of compound in water and in organic solvent
c)Fixed : Mass of compound, Volume water and organic solvent used.

9. Procedure :
1.Put half spatula of magnesium chloride, MgCl
2powder into the test tube.
2.Add 5 cm3 of distilled water into test tube and shake gently.
3.Observe the solubility of magnesium chloride, MgCl
2in water.
4.Repeat steps 1 to 3 using cyclohexane, C
6H
12as the solvent.
5.Repeat steps 1 to 4 and substitute magnesium chloride, MgCl
2with naphthalene, C
10H
8.
6.Record your observations on the solubility of compounds in Table 5.2.

10. Results :
Compound Solubilityin distilled waterSolubility in cyclohexane, C
6H
12
Magnesium chloride, MgCl
2
White solid dissolves in water.White solid did not dissolve in
cyclohexane, C
6H
12
Naphthalene, C
10H
8
White soliddid not dissolve in
water.
White solid dissolves in
cyclohexane, C
6H
12

11. C. Melting point and boiling point of compound
Hypothesis : Ionic compound has high boiling point and melting point whereas
covalent compound has low melting point and boiling point.
Variables :
a)Manipulated : Type of compound
b)Responding : Melting point and boiling point of compound
c)Fixed : Mass of compound used

12. Procedure :
1.Put half spatula of magnesium chloride, MgCl
2powder and naphthalene, C
10H
8into separate
test tube.
2.Heat both test tube in water bath as shown in Figure 5.23. for 10 to 15 minutes.
3.Observe and record the change in physical states and make inference of both substances in
Table 5.3.

13. Results :
Compound Observation Inference
Magnesium chloride,
MgCl
2
White solid remained
after 15 minutes.
High melting point
Naphthalene, C
10H
8 Whitesolid melts. Low melting point

14. Conclusion :
Discussion :
1.What type of compound is lead(II) bromide, PbBr
2, magnesium chloride, MgCl
2and
naphthalene, C
10H
8?
2.Predict the electrical conductivity, solubility, melting point and boiling point of sodium
chloride, NaCl.
Lead(II) bromide, PbBr2, and magnesium chloride, MgCl2 are ionic compounds whereas
napthalene, C10H8 is a covalent compound.
Sodium chloride, NaCl is an compound. Therefore sodium chloride can conduct electricity in
molten and aqueous form, dissolve in water but cannot dissolve in organic solvent and has has
high melting point and boiling point
Hypothesis is accepted.
1.Ionic compounds have high melting and boiling points, whereas covalent compounds have low
melting and boiling point.
2.Ionic compounds are usually soluble in water but insoluble in organic solvents. Covalent
compounds are usually insoluble in water but soluble in organic solvents.
3.Ionic compounds can conduct electricity in the molten state but cannot conduct electricity in the
solid state. Covalent compounds cannot conduct electricity in the solid and molten state.

15. Electrical
conductivity

16. Electric conductivity
•BasedonExperiment5.1,ioniccompounds andcovalent
compoundshavedifferentelectricalconductivity.
•Ioniccompoundscannotconductelectricityinthesolidstatebut
canconductelectricityinthemoltenstateandaqueoussolution.
•Covalentcompoundscannotconductelectricityinallstates

20. Solubility
in water and
organic solvent

21. Solubility in Water and Organic Solvent
•Mostioniccompoundsaresolubleinwaterbutarenotsolublein
organicsolvents.
•Mostcovalentcompoundsarenotsolubleinwaterbutaresoluble
inorganicsolvents.

22. Solubility in Water and Organic Solvent
•Whendissolvedinwater,watermoleculeshelptoovercome
electrostaticattractionforcebetweenionsandbreakdownthe
latticestructureofthesolidcompound.Asaresult,ionscanmove
freelyinwater.

23. 5.7.2Explain with examples the uses of ionic
and covalent compounds in daily life
State the uses of covalent compounds as solvents
5.7 Ionic and covalent compounds

24. Uses of Ionic Compounds and Covalent Compounds in Our Daily Lives
Most ionic compounds and covalent compounds used in our daily lives are in
the industrial sector, agriculture, medicine and domestic use.

25. Uses of Ionic Compounds and Covalent Compounds in Our Daily Lives
Most ionic compounds and covalent compounds used in our daily lives are in
the industrial sector, agriculture, medicine and domestic use.

26. Uses of Ionic Compounds and Covalent Compounds in Our Daily Lives
Most ionic compounds and covalent compounds used in our daily lives are in
the industrial sector, agriculture, medicineand domestic use.

27. Uses of Ionic Compounds and Covalent Compounds in Our Daily Lives
Most ionic compounds and covalent compounds used in our daily lives are in
the industrial sector, agriculture, medicineand domestic use.