Answer all questions Jawab semua soalan

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1 4541/ Answer all questions Jawab semua soalan 1. Diagram 1.1 shows the set-up of apparatus for an experiment to compare the hardness of a bronze and its pure metal, copper. Rajah 1.1 menunjukkan susunan radas bagi satu eksperimen untuk membandingkan kekerasan gangsa dan logam tulennya, kuprum. Thread [Benang] 1 kg weight [Pemberat 1 kg] Retort stand Kaki retort [] Cellophane tape Pita pelekat Steel ball bearing Bebola keluli Copper block [Bongkah ]kuprum] Diagram 1.1 Rajah 1.1 The experiment was carried out according the following steps: Eksperimen tersebut dijalankan berdasarkan langkah-langkah berikut: Step 1 Langkah 1: Step 2: Langkah 2: Step : Langkah : Step 4: Langkah 4: A steel ball bearing is taped onto the copper block. Satu bebola keluli dilekatkan di atas bongkah kuprum. A 1 kg weight is hung at a height of 50 cm above the copper block as shown in diagram 1.1 Pemberat 1 kg digantung pada ketinggian 50 cm di atas bongkah kuprum seperti ditunjukkan dalam rajah 1.1 The weight is allowed to drop onto the ball bearing. Pemberat dijatuhkan ke atas bebola keluli. The diameter of the dent made on the copper block was measured. Diameter lekukan yang terbentuk pada blok bongkah kuprum diukur.

2 Step 5: Langkah 5: Step 6: Langkah 6: Step1 to 4 are repeated on two other parts of the copper block in order to obtain an average value for the diameter of dents formed. Langkah 1 hingga 4 diulang pada dua bahagian lain bongkah kuprum untuk mendapatkan purata diameter lekukan yang terbentuk. Step 1 to 5 are repeated by the replacing the copper block with bronze block. Langkah 1 hingga 5 diulang untuk menggantikan bongkah kuprum dengan bongkah gangsa. Diagram 1.2 shows the shape of dents formed for the experiment. Rajah 1.2 menunjukkan lekuk yang terbentuk bagi eksperimen itu. Steel ball bearing Bebola keluli Copper block Blok kuprum Diagram 1.2 Rajah 1.2

3 4541/ Table 1.1 (a) shows the three dents formed on the copper block. Jadual 1.1 (a) menunjukkan tiga lekuk yang terhasil di atas bongkah kuprum. Sets Set Diagram of the dents formed Rajah lekuk yang terbentuk. Copper block Blok kuprum Diameter of the dent (cm) Diameter lekuk (cm) I... Copper block Blok kuprum II Copper block Blok kuprum... III... Table 1.1(a) Jadual 1.1(a)

4 Table 1.1 (b) shows the three dents formed on the bronze block. Jadual 1.1 (b) menunjukkan tiga lekuk yang terhasil diatas bongkah gangsa. Sets Set Diagram of the dents formed Rajah lekuk yang terbentuk. Bronze block Blok gangsa Diameter of the dent (cm) Diameter lekuk (cm) I... II Bronze block Blok gangsa... Bronze block Blok gangsa III Table 1.1 (b) Jadual 1.1 (b)...

5 5 4541/ (a) (i) By using a ruler given, measure the diameters of the dents made on copper and bronze blocks. Record all the diameters of the dents in Table 1.1(a) and 1.1 (b) Dengan menggunakan pembaris yang diberikan. Ukur diameter lekukan yang terbentuk pada bongkah kuprum dan gangsa. Rekod semua diameter lekukan pada jadual 1.1 (a) dan 1.1 (b). [ marks] [ markah] For Examiner s Use 1(a)(i) (ii) Construct a table to record the diameters of the dents and average diameter on copper and bronze blocks. Bina satu jadual bagi merekodkan diameter lekukan dan purata diameter untuk bongkah kuprum dan gangsa 1(a)(ii) [ marks] [ markah] (b) State one observation for this experiment. Nyatakan satu pemerhatian daripada eksperimen ini. 1(b) [ marks] [ markah] (c) Based on the average diameter of the dents copper and bronze blocks, state the inference that can be made. Berdasarkan purata diameter lekukan pada bongkah kuprum dan gangsa nyatakan inferens yang boleh dibuat. 1(c) [ marks] [ markah] 4541/@ 2016

6 6 4541/ (d) Based on this experiment, complete Table 1.2. Berdasarkan eksperimen ini, lengkapkan Jadual 1.2. For Examiner s Use Type of variable Jenis pemboleh ubah (i) Manipulated variable Pembolehubah dimanipulasikan:. (iii) Responding variable: Pembolehubah bergerak balas: Action to be taken Tindakan untuk diambil (ii) Method to manipulated variable: Cara memanipulasikan pembolehubah: (iv) What to observe in the responding variable: Apa yang diperhatikan bagi pemboleh ubah bergerak balas: (v) Fixed variable; Pembolehubah dimalarkan:.. (vi) Method to maintain the fixed variable: Cara menetapkan pembolehubah yang dimalarkan:... [6 marks] [6 markah] 1(d) /

7 7 4541/ For Examiner s Use (e) State the hypothesis for this experiment. Nyatakan hipotesis bagi eksperimen tersebut. 1(e) (f) [ marks] [ markah] State the operational definition of an alloy for the eksperiment. Nyatakan definisi secara operasi bagi aloi untuk eksperimen itu. 1(f) [ marks] [ markah] (g) State the relationship between diameter of dent and hardness of the material. Nyatakan hubungan antara diameter lekuk dengan kekerasan bahan.. 1(g). [ marks] [ markah] (h) Explain why there is a difference in diameter of the dents on copper and bronze blocks. Terangkan mengapa terdapat perbezaan diameter lekukan pada bongkah kuprum dan gangsa. [ marks] [ markah] 1(h) 4541/@ 2016

8 8 4541/ (i) The following is a list of materials: Berikut adalah senarai beberapa bahan: Brass Pewter Aluminium Loyang Puiter Aluminium Stainless steel Tin Iron Keluli tahan karat Timah Besi. Classify the following materials into pure metal and alloy. Kelaskan bahan-bahan ini kepada logam tulen dan aloi. Pure metal Logam tulen Alloy Aloi 1(i) [ marks] [ markah] Total /

9 9 4541/ 2. Experiment 1 : NaOH + HCl NaCl + H 2 O H= kjmol -1 Experiment II : NaOH + CH COOH CH COONa + H H= -55 kjmol -1 The value of the heat of neutralization for the reaction between sodium hydroxide solution and strong acid solution is higher than the value of the heat of neutralization for the reaction between sodium hydroxide solution and weak acid solution. Nilai haba peneutralan bagi tindak balas antara larutan natrium hidroksida dengan larutan asid kuat lebih tinggi daripada haba peneutralan larutan natrium hidroksida dengan larutan asid lemah. Based on the above statement, you are required to design an experiment to determine and compare the heat of neutralization between sodium hydroxide solution with a names strong acid solution and a weak solution. Berdasarkan pernyataan di atas, anda dikehendaki merancang eksperimen untuk menentukan haba peneutralan di antara larutan natrium hidroksida dengan satu larutan asid kuat dan satu larutan asid lemah. Your planning should be include the followings: Perancangan anda hendaklah mengandungi perkara-perkara berikut : (a) Problem Statement Pernyataan masalah (b) Hypothesis Hipotesis (c) All the variables Semua pemboleh ubah yang terlibat (d) List of materials and apparatus Senarai bahan dan alat radas (e) Tabulation of data Penjadualan data [17 marks] [17 markah] END OF QUESTION PAPER KERTAS SOALAN TAMAT 4541/@ 2016