laboratory guide for teacher
TRANSCRIPT
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8/22/2019 Laboratory Guide for Teacher
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LG 1 Penerbitan Pelangi Sdn
Kimia Tingkatan
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GuidedExperiment 1.1 Scientifc method
1. Remind students to add a little salt at a time into
the beaker. Make sure that all the salt added isdissolved beore any salt is added again.
2
InquiryExperiment 2.1 Diusion
1. Remind students that liquid bromine is toxic.
2. Make sure that students carry out the activity in
a ume chamber.
3. Use pure liquid bromine.
4. 1 mol dm3 potassium manganate(VII) solution isprepared by dissolving 158 g o solid potassium
manganate(VII) in distilled water and then make
up the volume o the solution to 1 dm3.
InquiryExperiment 2.2 The melting and reezing points o
naphthalene
1. Remind students that the level o naphthalenein the boiling tube should be below the level o
water in the beaker.
2. Make sure that the entire thermometer bulb is
submerged into the molten naphthalene and
does not touch the bottom or walls o the test
tube.
3. Remind students to stir the molten naphthalene
continuously with thermometer throughout the
activity.
3
InquiryExperiment 3.1 Empirical ormula
1. Use an electronic balance that measures to the
nearest 0.01 g.
2. Make sure that students remove the ox
layer on the surace o the magnesium rib
by rubbing it using a piece o sandpaper.
InquiryExperiment 3.2 Chemical equations
1. Lime water is prepared by dissolving calc
hydroxide powder in distilled water unt
saturated solution is obtained. Then lter
solution to remove the excess calcium hydroxpowder.
2. 0.2 mol dm3 lead(II) nitrate solution is prepa
by dissolving 66.2 g o solid lead(II) nitratdistilled water and then make up the volum
the solution to 1 dm3.
3. 0.2 mol dm3 potassium iodide solution is prepa
by dissolving 33.2 g o solid potassium iodid
distilled water and then make up the volumthe solution to 1 dm3.
4. In Activity A,(a) make sure that the test tube is clam
horizontally.
(b) ater heating, immediately disconnect
delivery tube so that the liquid is not suc
back into the hot test tube. The cold liqwill crack the test tube.
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PEKA 1 Chemical properties o Group 1elements
1. Use a pair o orceps to hold solid lithium, sod
or potassium and cut them using a knie.
not touch these alkali metals with bare ha
because they are very reactive.
2. Small pieces o lithium, sodium or potass
that are removed rom the paran oil in a bo
must be dried using lter paper beore they
used.
3. Oxygen gas is prepared by adding a small amo
o manganese(IV) oxide powder (catalyst) hydrogen peroxide solution (10 volumes) in a
bottomed fask. Oxygen gas is collected in a
jar by downward displacement o water.
4. Remind students to stand urther away rom
water trough when solid potassium is placed
the surace o the water because a very vigorreaction will occur.
Laboratory Guide for Teachers
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LG 2Penerbitan Pelangi Sdn. Bhd.
PELANGI Kimia Tingkatan 4
PEKA 2 Chemical properties o Group 17elements
1. Remind students that chlorine gas and bromine
vapour are very poisonous. When accidentally
contacted, the liquid bromine can cause lesions
on the skin.
2. Chlorine gas can be prepared by mixingconcentrated hydrochloric acid with solid
potassium manganate(VII) (without heating) in
a conical fask or fat-bottomed fask.
3. 2 mol dm3 sodium hydroxide solution is prepared
by dissolving 80.0 g o solid sodium hydroxide in
water to orm 1 dm3 solution.
4. Once the reaction between iron wool and halogen
vapour starts in Activity B, heating is stopped
because the reaction produces a lot o heatenergy which can keep the reaction going.
GuidedExperiment 4.1
Properties o the oxides o
elements in Period 3
1. Sulphur dioxide gas can be prepared by heating a
mixture o solid sodium sulphite and dilute nitric
acid.
Na2SO
3(s) + 2HNO
3(aq)
2NaNO3(aq) + H
2O(l) + SO
2(g)
2. 2 mol dm3 nitric acid is prepared by diluting
130 cm3 o concentrated nitric acid with distilled
water and make it to 1 dm3 solution.
3. 2 mol dm3 sodium hydroxide solution is prepared
by dissolving 80.0 g o solid sodium hydroxide in
water to orm 1 dm3 solution.
4. In Activity B, only a small amount o aluminium
oxide powder and silicon(IV) oxide powder are
used in each test.
InquiryExperiment 4.2
Colours o transition element
compounds
1. When dissolving the crystals in water, use onlya small amount o crystals and dissolve them in
5 cm3 o distilled water, lter the solution i a
clear solution is not obtained.
2. 2 mol dm3 ammonia solution is prepared by
diluting 140 cm3 o concentrated ammonia withdistilled water to orm 1 dm3 solution.
3. 2 mol dm3 sodium hydroxide solution is prepared
by dissolving 80.0 g o solid sodium hydroxide inwater to orm 1 dm3 solution.
4. Ammonia or sodium hydroxide solution is
added slowly, drop by drop, until a precipitate
appears.
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InquiryExperiment 5.1
Preparation o ionic compounds
1. Magnesium ribbon must be cleaned usin
sandpaper beore it is used in order to removthe oxide layer on its surace.
2. The oil on the surace o the sodium granule mu
be dried by rolling it on a piece o lter pape
beore it is used.
3. Chlorine gas can be prepared by mixinconcentrated hydrochloric acid with soli
potassium manganate(VII) (without heating) i
a conical fask or fat-bottomed fask. Chlorin
gas evolved is collected in a gas jar by upwar
displacement o air.
4. Iron lings must be in dry condition beore it used.
InquiryExperiment 5.2
Properties o ionic and covalent
compounds
1. In Activity A, only a small amount o magnesiumchloride or diethyl ether is dissolved in 5 cm3 owater or cyclohexane.
2. In Activity C, carbon electrodes must be cleaneusing sandpaper beore they are used.
3. In Activity C, the heating o liquid naphthalenmust be controlled so that the temperature othe liquid naphthalene does not rise too higbecause the vapour o naphthalene evolved easily burnt when ignited.
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InquiryExperiment 6.1
Electrolytes and non-electrolytes
1. 2 mol dm3 sodium hydroxide solution is prepare
by dissolving 80.0 g o solid sodium hydroxide i
distilled water to make a 1 dm3 solution.
2. The glucose solution is prepared by dissolvin90 g o glucose in distilled water and then makup the volume o the solution to 1 dm3.
3. 1 mol dm3 copper(II) sulphate solution
prepared by dissolving 250 g o solid CuSO4.5H
2
in distilled water and then make up the volum
o the solution to 1 dm3.
4. Clean the carbon electrodes with sandpapebeore they are used.
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LG 3 Penerbitan Pelangi Sdn
Kimia Tingkatan
5. Make sure that the students do not heat thenaphthalene strongly ater the naphthalenemelts because its vapour catches re easily.
InquiryExperiment 6.2
Electrolysis o molten lead(II)
bromide
1. Clean the carbon electrodes with sandpaper
beore they are used. 2. Make sure that the students carry out the activity
in a ume chamber.
3. Remind the students that bromine vapour istoxic.
InquiryExperiment 6.3
Electrolysis o copper(II) sulphate
solution and dilute sulphuric acid
using carbon electrodes
1. 0.1 mol dm3 copper(II) sulphate solution isprepared by dissolving 25 g o solid CuSO
4.5H
2O
in distilled water and then make up the volumeo the solution to 1 dm3.
2. 0.1 mol dm3 sulphuric acid is prepared by diluting5.5 cm3 o concentrated sulphuric acid withdistilled water and make it to 1 dm3 solution.
3. Clean the carbon electrodes with sandpaperbeore they are used.
GuidedExperiment 6.4
Factors that determine the
selective discharge o ions at
electrodes during the electrolysis
o an aqueous solution
1. 0.1 mol dm3 copper(II) nitrate solution is prepared
by dissolving 24.2 g o solid Cu(NO3)
2.3H
2O in
distilled water and then make up the volume othe solution to 1 dm3.
2. 0.1 mol dm3 sodium sulphate solution is prepared
by dissolving 14.2 g o solid sodium sulphate indistilled water and then make up the volume o
the solution to 1 dm3.
3. 2 mol dm3 hydrochloric acid is prepared bydiluting 170 cm3 o concentrated hydrochloric
acid with distilled water to make a 1 dm3
solution.
4. 0.001 mol dm3 hydrochloric acid is prepared bydiluting 1 cm3 o 2 mol dm3 hydrochloric acid
with distilled water to make a 2 dm3 solution.
5. 0.1 mol dm3
copper(II) sulphate solution isprepared by dissolving 25 g o solid CuSO
4.5H
2O
in distilled water and then make up the volumeo the solution to 1 dm3.
6. Clean the carbon electrodes with sandpaperbeore they are used.
7. Use an electronic balance that measures to the
nearest 0.01 g.
8. Remind the students to dry the electrodes be
weighing the electrodes.
GuidedExperiment 6.5 Purifcation o metals
1. 1 mol dm3 copper(II) sulphate solution
prepared by dissolving 250 g o solid CuSO4.5
in distilled water and then make up the voluo the solution to 1 dm3.
2. Remind students to clean the copper plates w
sandpaper beore they are used.
GuidedExperiment 6.6 Electroplating o metals
1. 1 mol dm3 copper(II) sulphate solution
prepared by dissolving 250 g o solid CuSO4.5
in distilled water and then make up the voluo the solution to 1 dm3.
2. Remind students to clean the copper strip
iron spoon using sandpaper beore they used.
3. Remind students to maintain a constant 0.2
current throughout the experiment by adjus
the current using the rheostat.
4. Make sure that the entire spoon is submer
in the electrolyte.
GuidedExperiment 6.7 The simple voltaic cell
1. 1 mol dm3 sodium chloride solution is prepa
by dissolving 58.5 g o solid sodium chlorid
distilled water and then make up the volumthe solution to 1 dm3.
2. Make sure that the students clean the cop
plate and magnesium ribbon with sandpabeore they are used.
GuidedExperiment 6.8 The construction o electrochem
series based on potential
dierences between metals
1. 0.1 mol dm3 copper(II) sulphate solutioprepared by dissolving 25 g o solid CuSO
4. 5
in distilled water and then make up the volu
o the solution to 1 dm3.
2. Dip the lead strip into concentrated hydrochlacid beore it is used.
3. Clean other metals with sandpaper beore t
are used.
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LG 4Penerbitan Pelangi Sdn. Bhd.
PELANGI Kimia Tingkatan 4GuidedExperiment 6.9
The construction o electrochemical
series based on the principle o
displacement o metals
1. The solutions should be prepared as ollows:
(a) 242 g dm3 Cu(NO3)2.3H
2O
(b) 331 g dm3 lead(II) nitrate
(c) 180 g dm3 iron(II) nitrate
(d) 189 g dm3
zinc nitrate(e) 148 g dm3 magnesium nitrate
2. Dip the lead strip into concentrated hydrochloric
acid beore it is used.
3. Clean the other metals with sandpaper beore
they are used.
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PEKA 3 The role o water in showing the
properties o acids
1. Make sure that the glacial ethanoic acid is
completely dry. This can be done by adding a
little ethanoic anhydride, (CH3CO)
2O to a bottle o
glacial ethanoic acid a day beore the experiment(1 cm3 o ethanoic anhydride to 100 cm3 o glacial
ethanoic acid).
2. Glacial ethanoic acid is corrosive. Be careulwhen handling it.
3. 2 mol dm3 aqueous ethanoic acid can be
prepared by diluting 116 cm3 o glacial ethanoic
acid in distilled water and then make it to 1 dm3
solution. 4. Ethanoic acid in dry propanone is prepared by
dissolving 116 cm3 o glacial etanoic acid in drypropanone and then make it to 1 dm3 solution.
5. Make sure that the blue litmus paper used is
dry.
GuidedExperiment 7.1
The role o water in showing the
properties o alkalis
1. Barium hydroxide powder must be dried in anoven and then kept in a desiccator beore it is
used.
2. Make sure that the red litmus paper used isdry.
PEKA 4 The pH values and molarity o acidsand alkalis
1. 0.1 mol dm3 hydrochloric acid is prepared b
diluting 8.5 cm3 o concentrated hydrochlor
acid with distilled water and then make it t
1 dm3 solution.
2. 0.01 mol dm3 hydrochloric acid is prepared b
diluting 50.0 cm3
o 0.1 mol dm3
hydrochloric aciwith distilled water and then make it to 500 cmsolution.
3. 0.001 mol dm3 hydrochloric acid is prepared b
diluting 50.0 cm3 o 0.01 mol dm3 hydrochlor
acid with distilled water and then make it t500 cm3 solution.
4. 0.0001 mol dm3 hydrochloric acid is prepared b
diluting 50.0 cm3 o 0.001 mol dm3 hydrochloracid with distilled water and then make
500 cm3 solution.
5. 0.00001 mol dm3 hydrochloric acid is prepared bdiluting 50.0 cm3 o 0.0001 mol dm3 hydrochlor
acid with distilled water and then make it t500 cm3 solution.
6. 0.1 mol dm3 sodium hydroxide solution prepared by dissolving 4.0 g o solid sodium
hydroxide in distilled water and make it to 1 dm
solution.
7. 0.01 mol dm3 sodium hydroxide solution
prepared by diluting 50.0 cm3 o 0.1 mol dm
sodium hydroxide solution with distilled wate
and make it to 500 cm3 solution.
8. 0.001 mol dm3 sodium hydroxide solution
prepared by diluting 50.0 cm3 o 0.01 mol dm
sodium hydroxide solution with distilled wate
and then make it to 500 cm3 solution. 9. 0.0001 mol dm3 sodium hydroxide solution
prepared by diluting 50.0 cm3 o 0.001 mol dm
sodium hydroxide solution with distilled wate
and then make it to 500 cm3 solution.
10. 0.00001 mol dm3 sodium hydroxide solution
prepared by diluting 50.0 cm3 o 0.0001 mol dm
sodium hydroxide solution with distilled wate
and then make it to 500 cm3 solution.
InquiryExperiment 7.2 Acid-base titration
1. 0.1 mol dm3 sulphuric acid is prepared by dilutin
5.5 cm3 o concentrated sulphuric acid witdistilled water and make it to 1 dm3 solution.
2. 0.2 mol dm3 potassium hydroxide solution
prepared by dissolving 11.2 g o solid potassium
hydroxide in distilled water and then make it t1 dm3 solution.
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Kimia Tingkatan 3. Phenolphthalein indicator is prepared by
dissolving 0.20 g solid phenolphthalein in 120 cm3
o 95% ethanol. 80 cm3 o distilled water is then
added and the mixture is shaken well.
4. Remind students that burette readings must be
read to the accuracy o 0.05 cm3.
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InquiryExperiment 8.1 Preparation o a soluble salt rom
the reaction o an acid with analkali
1. 2 mol dm3 hydrochloric acid is prepared bydiluting 170 cm3 o concentrated hydrochloric
acid with distilled water and then make it to
1 dm3 solution.
2. 2 mol dm3 potassium hydroxide solution isprepared by dissolving 112.0 g o solid potassium
hydroxide in distilled water and then make it to
1 dm3 solution.
3. Phenolphthalein indicator is prepared by
dissolving 0.20 g solid phenolphthalein in 120 cm3
o 95% ethanol. 80 cm3 o distilled water is then
added and the mixture is shaken well.
4. Burette readings must be read to the accuracy
o 0.05 cm3.
InquiryExperiment 8.2 Preparation o a soluble salt rom
the reaction o an acid with ametal oxide
1. 2 mol dm3 nitric acid is prepared by diluting
130 cm3 o concentrated nitric acid with distilled
water and make it to 1 dm3 solution.
2. Remind students to warm the dilute nitric acid
as this will speed up the reaction between nitric
acid and copper(II) oxide.
InquiryExperiment 86.3 Preparation o insoluble salts
1. 0.5 mol dm3 lead(II) nitrate solution is prepared
by dissolving 165.5 g o solid lead(II) nitrate in
distilled water and make it to 1 dm3 solution.
2. 1.0 mol dm3 potassium iodide solution is prepared
by dissolving 166.0 g o solid potassium iodide in
distilled water and make it to 1 dm3 solution.
3. 0.5 mol dm3 potassium chromate(VI) solution is
prepared by dissolving 97.0 g o solid potassium
chromate(VI) in distilled water and make it to1 dm3 solution.
4. 0.5 mol dm3 barium nitrate solution is prepa
by dissolving 130.5 g o solid barium nitrat
distilled water and make it to 1 dm3 solution
5. 0.5 mol dm3 sodium sulphate solution is prepa
by dissolving 161 g o hydrated sodium sulphadistilled water and make it to 1 dm3 solution
PEKA 5 Construction o ionic equations usinthe continuous variation method
1. 0.5 mol dm3 lead(II) nitrate solution is prepa
by dissolving 165.5 g o solid lead(II) nitrat
distilled water and make it to 1 dm3 solution
2. 0.5 mol dm3 potassium chromate(VI) solutio
prepared by dissolving 97.0 g o solid potass
chromate(VI) in distilled water and make i1 dm3 solution.
3. Make sure that all the seven test tubes used
o the same size, diameter and height.
4. Measure the height o the precipitate to decimal place in cm.
InquiryExperiment 8.4 Action o heat on carbonate an
nitrate salts
1. Lime water is prepared by dissolving calc
hydroxide powder in distilled water until
powder cannot dissolve anymore. Then,
solution is ltered to obtain the ltrate or l
water.
2. The heating o carbonate and nitrate salts m
be done with a very strong fame. 3. Remind students that the test tube contain
solid must be held horizontally during heati
4. Make sure that students wet the litmus pa
with water beore using it to test or gases.
5. Make sure dry test tubes are used or the hea
o each solid.
6. Students must record the colour o the resi
when hot and when cold.
7. Warn students not to inhale the brown
evolved because it is poisonous.
InquiryExperiment 8.5 Comfrmatory tests or anions
aqueous solution
1. Solutions o anions used have the concentratio
approximately 1 mol dm3, or example, Na2CO
106 g dm3, Na2SO
4(aq) 142 g dm3, NaCl
58.5 g dm3 and NaNO3(aq) 85 g dm3.
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PELANGI Kimia Tingkatan 4
2. 2 mol dm3 hydrochloric acid is prepared by
diluting 170 cm3 o concentrated hydrochloric
acid with distilled water and then make it to
1 dm3 solution.
3. 2 mol dm3 nitric acid is prepared by diluting
130 cm3 o concentrated nitric acid with distilled
water and make it to 1 dm3 solution.
4. 1 mol dm
3
sulphuric acid is prepared by diluting55 cm3 o concentrated sulphuric acid with
distilled water and make it to 1 dm3 solution.
5. Reagents used should have the ollowing
concentrations:
(a) Iron(II) sulphate solution 278 g dm 3
FeSO4.7H
2O
(b) Silver nitrate solution 17 g dm3 AgNO3
(c) Barium chloride solution 208 g dm3 BaCl2
6. Lime water is prepared by dissolving calcium
hydroxide powder in distilled water until the
powder cannot dissolve anymore. Then, the
solution is ltered to obtain the ltrate or lime
water.
InquiryExperiment 8.6 Tests or cations in aqueous
solutions
1. Solutions o cations are prepared according to
the ollowing concentrations:
(a) Sodium nitrate solution 85 g dm3 NaNO3
(b) Ammonium chloride solution 53.5 g dm3
NH4Cl
(c) Calcium nitrate solution 164 g dm 3
Ca(NO3)2
(d) Magnesium nitrate solution 256 g dm3
Mg(NO3)2.6H2O(e) Aluminium nitrate solution 375 g dm3
Al(NO3)3.9H
2O
() Zinc nitrate solution 297 g dm 3
Zn(NO3)2.6H
2O
(g) Iron(II) sulphate solution 278 g dm 3FeSO
4.7H
2O
(h) Iron(III) chloride solution 162.5 g dm3 Fe-
Cl3
(i) Lead(II) nitrate solution 331 g dm3
Pb(NO3)
2
(j) Copper(II) sulphate solution 250 g dm3CuSO
4.5H
2O
2. 2 mol dm3 sodium hydroxide solution is prepared
by dissolving 80.0 g o solid sodium hydroxide indistilled water and make it to 1 dm3 solution.
3. 2 mol dm3 ammonia solution is prepared by
diluting 140 cm3 o concentrated ammonia withdistilled water and make it to 1 dm3 solution.
InquiryExperiment 8.7 Comfrmatory tests or
ammonium ion, iron(II) ion,
iron(III) ion and lead(II) ion
1. The reagents used are prepared according to th
ollowing concentrations:
(a) Sodium hydroxide solution 80 g dm
NaOH
(b) Potassium hexacyanoerrate(II) solutio 50 g dm3 K
4Fe(CN)
6
(c) Potassium hexacyanoerrate(III) solutio
50 g dm3 K3Fe(CN)
6
(d) Potassium thiocyanate solution 50 g dm
KSCN
(e) Potassium iodide solution 83 g dm3 KI() Iron(II) sulphate solution 139 g dm
FeSO4.7H
20
(g) Iron(III) chloride solution 81.3 g dm3 FeC
(h) Lead(II) nitrate solution 165.5 g dm
Pb(NO3)
2
(i) Ammonium chloride solution 53.5 g dmNH
4
Cl
2. Remind students that lead(II) iodide and lead(I
chloride are soluble in hot water but insoluble icold water.
InquiryExperiment 8.8 Identifcation o cations and
anions o unknown salts
1. Put two spatulaul o solid aluminium nitrate inta small plastic bag labelled K1.
2. Reagent bottles containing the ollowing solution
are prepared:(a) 2 mol dm3 dilute nitric acid
(b) 2 mol dm
3
dilute hydrochloric acid(c) 1 mol dm3 dilute sulphuric acid
(d) 80 g dm3 sodium hydroxide solution
(e) 2 mol dm3 ammonia solution
() Lime water(g) 104 g dm3 barium chloride solution
(h) 17 g dm3 silver nitrate solution
(i) 139 g dm3 iron(II) sulphate solution
(j) 83 g dm3 potassium iodide solution
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InquiryExperiment 9.1 Preparation o ammonium
ertiliser
1. 1 mol dm3 sulphuric acid is prepared by dilutin
55 cm3 o concentrated sulphuric acid wit
distilled water and make it to 1 dm3 solution.
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Kimia Tingkatan 2. 2 mol dm3 ammonia is prepared by diluting
140 cm3 o concentrated ammonia with distilled
water to make a 1 dm3 o solution.
3. To make sure that the ltrate is saturated enough
to crystallise, dip a small amount o the ltrate
with the end o a cold, dry glass rod. I the ltrate
is saturated, crystals will orm on the glass rod.
PEKA 6 Hardness o pure metal and its alloy
1. Make sure that students measure the diameter o
the dents in centimetre to the nearest 0.05 cm.
2. Make sure that the same size o ball bearings is
used throughout the experiment.
GuidedExperiment 9.2
Rate o corrosion o iron, steel
and stainless steel
1. Clean all the nails with sandpaper beore t
are used.
2. 0.2 mol dm3 potassium hexacyanoerratesolution is prepared by dissolving 65.8 g o s
potassium hexacyanoerrate(III) in distilled w
and make up the volume o solution to 1 dm