SKEMA MARKAH
Question No.
PPT KIMIA TING. 5 (2018) KERTAS 3
Mark Scheme
Mark
Able to record all readings correctly to one decimal place with unit Answer: 17.0s, 20.0s, 25.0s, 33.0s, 50.0s 1(a)
3
Able to record 4 readings correctly / all readings correctly but without decimal place / without unit
2
Able to record 3 readings correctly but without decimal place / without unit
1
No response given / Wrong response
0
Question No.
Mark Scheme
Mark
Able to state the observation correctly Sample answer: ‘X’ mark disappear from sight Tanda ‘X’ hilang dari penglihatan // Precipitate / solid is formed Mendakan / pepejal terbentuk //
3
Solid covers ‘X’ mark Pepejal menutupi tanda ‘X’ Able to state observation less correctly 1(b)(i)
Sample answer: ‘X’ mark disappear Tanda ‘X’ hilang
2
Able to state an idea of observation Sample answer: Precipitate / Mendakan // 1 Solid / Pepejal // Reaction occurs / Tindak balas berlaku No response given / Wrong response
0
1
SKEMA MARKAH
Question No.
PPT KIMIA TING. 5 (2018) KERTAS 3
Mark Scheme
Mark
Able to state the inference correctly Sample answer: Sulphur is formed / Sulfur terbentuk
3
Able to state inference less correctly
1(b)(ii)
Sample answer: Acid reacts with sodium thiosulphate Asid bertindak balas dengan natrium tiosulfat
2
Able to state an idea of inference Sample answer: Reaction occurs / Tindak balas berlaku //
1
Rate of reaction is affected by temperature / Kadar tindak balas dipengaruhi oleh suhu No response given / Wrong response Question No.
0
Mark Scheme
Mark
Able to complete the table with all correct values with 2 decimal places for 1/time
1(c)
Concentration of sodium thiosulphate solution / mol dm-3 Time / s Kepekatan larutan natrium tiosulfat Masa / s / mol dm-3 17.0 0.24 20.0 0.20 25.0 0.16 33.0 0.12 50.0 0.08 Able to complete the table with 4 correct values Able to complete the table with 3 correct values No response given / Wrong response
1 / s-1 Time 1 / s-1 Masa 0.06 0.05 0.04 0.03 0.02
3
2 1 0
2
SKEMA MARKAH
Question No.
PPT KIMIA TING. 5 (2018) KERTAS 3
Mark Scheme
Mark
Able to state all 3 variables correctly Sample answer: Manipulated variable : Concentration of sodium thiosulphate solution / Kepekatan larutan natrium tiosulfat Responding variable : Time taken for ‘X’ mark to disappear from sight Masa yang diambil untuk tanda ‘X’ hilang dari Penglihatan // Rate of reaction / Kadar tindak balas 1(d)
3
Fixed variable : Volume and concentration of sulphuric acid Isi padu dan kepekatan asid sulfurik // Temperature / Suhu // Size of conical flask / Saiz kelalang kon // Type of acid / Jenis asid Able to state any 2 variables correctly Able to state any 1 variable correctly No response given / Wrong response
2 1 0
3
SKEMA MARKAH
Question No.
PPT KIMIA TING. 5 (2018) KERTAS 3
Mark Scheme
Mark
Able to state the relationship between manipulated variable and responding variable correctly with direction Sample answer: The higher / lower the concentration of sodium thiosulphate solution, the higher / lower the rate of reaction Semakin tinggi / rendah kepekatan larutan natrium tiosulfat, semakin tinggi / rendah kadar tindak balas //
3
The higher / lower the concentration of sodium thiosulphate solution, the shorter / longer the time taken for the ‘X’ mark to disappear from sight Semakin tinggi / rendah kepekatan larutan natrium tiosulfat, semakin singkat / lama masa yang diambil untuk tanda ‘X’ hilang dari penglihatan Able to state the relationship between manipulated variable and responding variable less correctly 1(e)
Sample answer: The higher / lower the concentration of sodium thiosulphate solution, the faster / slower the rate of reaction Semakin tinggi / rendah kepekatan larutan natrium tiosulfat, semakin cepat / lambat kadar tindak balas //
2
The higher / lower the concentration of sodium thiosulphate solution, the shorter / longer the time taken for the ‘X’ mark to disappear Semakin tinggi / rendah kepekatan larutan natrium tiosulfat, semakin singkat / lama masa yang diambil untuk tanda ‘X’ hilang Able to state an idea of hypothesis Sample answer Concentration affects rate of reaction Kepekatan mempengaruhi kadar tindak balas //
1
When concentration change, rate of reaction change Apabila kepekatan berubah, kadar tindak balas berubah No response given / Wrong response
0
4
SKEMA MARKAH
Question No.
PPT KIMIA TING. 5 (2018) KERTAS 3
Mark Scheme
Mark
Able to draw a graph of concentration against 1/time showing the following aspects: 1. 2. 3. 4. 5.
The axes are labelled correctly with unit Uniform scale Size of graph is at least 50% of the graph paper All points are transferred correctly Straight line
Sample answer:
3 1(f)
Able to draw a graph of concentration against 1/time showing the following aspects:
2
1. The axes are labelled correctly with unit 5
SKEMA MARKAH
PPT KIMIA TING. 5 (2018) KERTAS 3
2. Uniform scale 3. All points are transferred correctly 4. Straight line Able to draw a graph of concentration against 1/time showing the following aspects: 1. The axes are labelled correctly without unit 2. Straight line No response given / Wrong response Question No.
Mark Scheme
1
0 Mark
Able to state the relationship between concentration of sodium thiosulphate solution and the rate of reaction correctly Sample answer: The higher / lower the concentration of sodium thiosulphate solution, the higher / lower the rate of reaction Semakin tinggi / rendah kepekatan larutan natrium tiosulfat, semakin tinggi / rendah kadar tindak balas //
3
When the concentration of sodium thiosulphate solution increases / decreases, the rate of reaction increases / decreases Apabila kepekatan larutan natrium tiosulfat bertambah / berkurang, kadar tindak balas bertambah / berkurang
1(g)(i)
Able to state the relationship between concentration of sodium thiosulphate solution and the rate of reaction less correctly Sample answer: The rate of reaction is directly proportional to the concentration of sodium thiosulphate solution Kadar tindak balas berkadar terus dengan kepekatan larutan natrium tiosulfat The higher the concentration of sodium thiosulphate solution / reactant, the lower the rate of reaction Semakin tinggi kepekatan larutan natrium tiosulfat / bahan tindak balas, semakin rendah kadar tindak balas //
2
The lower the concentration of sodium thiosulphate solution, the higher the rate of reaction Semakin rendah kepekatan larutan natrium tiosulfat, semakin tinggi kadar tindak balas // 6
SKEMA MARKAH
PPT KIMIA TING. 5 (2018) KERTAS 3
When the concentration of sodium thiosulphate solution increases / decreases, the rate of reaction decreases Apabila kepekatan larutan natrium tiosulfat bertambah, kadar tindak balas berkurang When the concentration of sodium thiosulphate solution decreases / decreases, the rate of reaction increases Apabila kepekatan larutan natrium tiosulfat berkurang, kadar tindak balas bertambah Able to give a relevant idea Sample answer Rate of reaction is affected by concentration Kadar tindak balas dipengaruhi oleh kepekatan // Rate of reaction is changed by concentration Kadar tindak balas diubah oleh kepekatan //
1
Rate of reaction is inversely proportional to concentration Kadar tindak balas berkadar songsang dengan kepekatan No response given / Wrong response
0
7
SKEMA MARKAH
Question No.
PPT KIMIA TING. 5 (2018) KERTAS 3
Mark Scheme
Mark
Able to fulfil all of the following criteria: 1. Show on the graph, the way to obtain 1/time 2. State the time 3. State the unit Sample answer:
3 1(g)(ii)
1/time = 0.055 s-1 Time = 1/0.055 = 18.18 s / 18.2 s Able to fulfil any 2 criteria Able to fulfil any 1 criteria No response given / Wrong response
2 1 0 8
SKEMA MARKAH
Question No.
PPT KIMIA TING. 5 (2018) KERTAS 3
Mark Scheme
Mark
Able to state the operational definition correctly based on the following criteria: 1. What is done 2. What is observed Sample answer: Time taken for ‘X’ mark to disappear from sight when sulphuric acid is added to sodium thiosulphate solution Masa yang diambil untuk tanda ‘X’ hilang dari penglihatan apabila asid sulfurik dimasukkan ke dalam larutan natrium tiosulfat 1(h)
3
Able to state the operational definition less correctly Sample answer: Time taken for ‘X’ mark to disappear Masa yang diambil untuk tanda ‘X’ hilang
2
Able to give an idea for the operational definition
Question No.
Sample answer: Time for reaction to occur / Masa untuk tindak balas berlaku
1
No response given / Wrong response
0
Mark Scheme
Mark
Able to classify the reactions correctly Answer:
1(i)
Slow reaction Fast reaction Tindak balas perlahan Tindak balas cepat • Rusting • Neutralisation Pengaratan Peneutralan • Fermentation • Combustion Penapaian Pembakaran • Corrosion • Displacement Kakisan Penyesaran Able to classify any 4 reactions correctly Able to classify any 3 reaction correctly or reverse classification No response given / Wrong response
3
2 1 0 9
SKEMA MARKAH
Question No.
PPT KIMIA TING. 5 (2018) KERTAS 3
Mark Scheme
Mark
Able to state the problem statement correctly Sample answer: How to determine the electrical conductivity of [named ionic compound eg. sodium chloride] and [named covalent compound eg. glucose] in water? // Bagaimanakah menentukan kekonduksian elektrik [sebatian ion yang dinamakan, cth. natrium klorida] dan [sebatian kovalen yang dinamakan, cth. glukosa] dalam air?
3
Able to state the problem statement less accurately Sample answer: How to determine the electrical conductivity of ionic compound and covalent compound in water? // Bagaimanakah menentukan kekonduksian elektrik sebatian ion dan sebatian kovalen dalam air? 2(a)
2
a: To investigate the electrical conductivity of ionic and covalent compounds in water Untuk mengkaji kekonduksian elektrik bagi sebatian ion dan kovalen dalam air Able to have an idea of the problem statement Sample answer: How to determine the electrical conductivity of different compounds? // Bagaimanakah menentukan kekonduksian elektrik sebatian yang berbeza?
1
a: To investigate the electrical conductivity of ionic and covalent compounds Untuk mengkaji kekonduksian elektrik bagi sebatian ion dan kovalen No response given / Wrong response
0
10
SKEMA MARKAH
Question No.
PPT KIMIA TING. 5 (2018) KERTAS 3
Mark Scheme
Mark
Able to state all 3 variables correctly Sample answer: Manipulated variable : Ionic and covalent compounds Sebatian ion dan kovalen // Sodium chloride and glucose Natrium klorida dan glukosa
2(b)
Responding variable : Electrical conductivity / Kekonduksian elektrik// Condition of bulb / Keadaan mentol // Ammeter reading / Bacaan ammeter // Deflection of ammeter needle / Pesongan jarum ammeter
3
Fixed variable : Type of electrode / Jenis elektrod // Water / air Able to state any 2 variables correctly
2
Able to state any 1 variable correctly
1
No response given / Wrong response
0
11
SKEMA MARKAH
Question No.
PPT KIMIA TING. 5 (2018) KERTAS 3
Mark Scheme
Mark
Able to state the relationship between manipulated variable and responding variable correctly with direction Sample answer: Ionic compounds can conduct electricity in water whereas covalent compounds cannot conduct electricity Sebatian ion boleh mengkonduksikan elektrik dalam air manakala sebatian kovalen tidak boleh mengkonduksikan elektrik
3
Able to state the relationship between manipulated variable and responding variable less correctly
2(c)
Sample answer: Ionic compounds can conduct electricity whereas covalent compounds cannot conduct electricity Sebatian ion boleh mengkonduksikan elektrik manakala sebatian kovalen tidak boleh mengkonduksikan elektrik
2
Able to state an idea of hypothesis Sample answer Some compounds can conduct electricity, some cannot Sesetengah sebatian boleh mengkonduksikan elektrik, sesetengah tidak boleh // Electrical conductivity of different compounds are different Kekonduksian elektrik sebatian berbeza adalah berbeza // Electrical conductivity depends on the type of compound Kekonduksian elektrik bergantung kepada jenis sebatian No response given / Wrong response
1
0
12
SKEMA MARKAH
Question No.
PPT KIMIA TING. 5 (2018) KERTAS 3
Mark Scheme
Mark
Able to list all apparatus and materials 1. Sodium chloride / Natrium klorida 2. Glucose / glukosa 3. Water / air 4. Beaker / bikar 5. Ammeter / ammeter // bulb / mentol 6. Connecting wire and clip / wayar penyambung dan klip 7. Carbon electrodes / elektrod karbon 8. Spatula / spatula 9. Measuring cylinder / silinder penyukat 10. Glass rod / rod kaca 11. Battery / bateri // dry cell / sel kering // power supply / sumber kuasa
3
OR
2(d)
1. Sodium chloride solution / Larutan natrium klorida 2. Glucose solution / larutan glukosa 3. Beaker / bikar 4. Ammeter / ammeter // bulb / mentol 5. Connecting wire and clip / wayar penyambung dan klip 6. Carbon electrodes / elektrod karbon 7. Measuring cylinder / silinder penyukat 8. Battery / bateri // dry cell / sel kering // power supply / sumber kuasa Able to list apparatus and materials less accurately Sample answer: 1. Sodium chloride / Natrium klorida 2. Glucose / glukosa 3. Water / air 4. Beaker / bikar 5. Ammeter / ammeter // bulb / mentol 6. Connecting wire and clip / wayar penyambung dan klip 7. Carbon electrodes / elektrod karbon
2
Able to give an idea of apparatus and materials Sample answer 1. Sodium chloride / Natrium klorida 2. Glucose / glukosa 3. Water / air
1
13
SKEMA MARKAH
PPT KIMIA TING. 5 (2018) KERTAS 3
4. Beaker / bikar 6. Connecting wire and clip / wayar penyambung dan klip 7. Carbon electrodes / elektrod karbon No response given / Wrong response
Question No.
Mark Scheme
0
Mark
Able to state all steps of procedure correctly
2(e)
1. Pour [50 – 250] cm3 of water into a beaker Tuang [50 – 250] cm3 air ke dalam bikar 2. Add one spatula of sodium chloride Tambah satu spatula natrium klorida 3. Stir the mixture Kacau campuran 4. Immerse 2 carbon electrodes Rendamkan 2 elektrod karbon 5. Connect the electrodes to the ammeter / bulb Sambungkan elektrod kepada ammeter / mentol 6. Record the ammeter reading Rekod bacaan ammeter // Observe the deflection of ammeter needle / condition of bulb Perhatikan pesongan jarum ammeter / keadaan mentol 7. Repeat steps 1 – 6 by using glucose to replace sodium chloride Ulang langkah 1 – 6 menggunakan glukosa bagi menggantikan natrium klorida
3
Able to state steps 1, 2, 4, 5, 7
2
Able to state steps 1, 2, 4, 5
1
No response given / Wrong response
0
14
SKEMA MARKAH
PPT KIMIA TING. 5 (2018) KERTAS 3
Question No.
Mark Scheme
Mark
Able to construct a table that consists of: 1. Headings for manipulated and responding variables 2. Complete list of types of compound
2(e)
Types of compound Observation / Electrical conductivity Jenis sebatian Pemerhatian / Kekonduksian elektrik Ionic compound Sebatian ion // Sodium chloride Natrium klorida Covalent compound Sebatian kovalen // Glucose Glukosa Able to construct a table that consists of: 1. Headings for manipulated and responding variables Types of compound Jenis sebatian
Observation / Electrical conductivity Pemerhatian / Kekonduksian elektrik
No response given / Wrong response
2
1
0
END OF ANSWER SCHEME SKEMA JAWAPAN TAMAT
15