PEPERIKSAAN IJAZAH SARJANA MUDA SAINS DENGAN PENDIDIKAN EXAMINATION FOR THE DEGREE OF BACHELOR OF SCIENCE WITH EDUCATION

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1 UIVERSITI MALAYA UIVERSITY OF MALAYA PEPERIKSAA IJAZAH SARJAA MUDA SAIS DEGA PEDIDIKA EXAMIATIO FOR THE DEGREE OF BACHELOR OF SCIECE WITH EDUCATIO SESI AKADEMIK 2010/2011 : SEMESTER 1 ACADEMIC SESSIO 2010/2011 : SEMESTER 1 SCEP1252 : KIMIA ASAS I BASIC CHEMISTRY I ovember/ Disember 2010 ovember/ December 2010 MASA : 2 jam TIME : 2 hours ARAHA KEPADA CALO : ISTRUCTIOS TO CADIDATES : Kertas soalan ini mengandungi Bahagian A, B dan C. This paper consists of Section A, B and C. Jawab soalan mengikut arahan yang diberikan dalam setiap bahagian. Questions should be answered according to the instructions given in each section. (Kertas soalan ini mengandungi 10 soalan dalam 9 halaman yang dicetak) (This question paper consists of 10 questions on 9 printed pages)

2 SCEP1252/02 Jawab semua soalan di dalam bahagian ini. Answer all questions in this section. BAHAGIA A (33 MARKAH) SECTIO A (33 MARKS) 1. ama IUPAC sebatian organik berikut adalah tidak betul. Berikan nama IUPAC yang betul. The following IUPAC names for organic compounds are incorrect. Give the correct IUPAC name. i. 4,5-Dikloro-bromobenzena 4,5-Dichloro-bromobenzene ii. cis-5-oktun-3-ena cis-5-octyn-3-ene (3 markah / marks) 2. Yang manakah di antara sebatian berikut merupakan sebatian aromatik dan yang manakah bukan sebatian aromatik? Jelaskan. Which of the following compounds are aromatic and which are not? Explain. (A) (B) (C) H H (D) (E) (10 markah / marks)

3 SCEP1252/03 3. Jawab semua soalan berikut: Answer all questions below: a. Minyak sayuran adalah sensitif kepada haba disebabkan oleh tindak balas radikal asid oleik dengan oksigen. Tunjukkan tempat yang paling reaktif dalam struktur asid oleik untuk tindak balas radikal dengan menyatakan nombor atom karbon mengikut penomboran IUPAC. Jelaskan dengan memberikan formula struktur radikal. The heat sensitivity of vegetable oil is caused by radical reactions of oleic acid with oxygen. Indicate the most reactive sites of oleic acid for radical reactions by providing the number(s) of the carbon-atom(s) according to IUPAC numbering. Explain it by providing the structural formulas of the radicals. H 3 C O OH b. Beri mekanisme tindak balas penukargantian radikal siklopentana dengan klorin menggunakan formula struktur dan tunjukkan semua langkah secara berasingan. Bagaimana tindak balas radikal berbeza dari kebanyakan tindak balas lain? Provide the reaction mechanism of the radical substitution of cyclopentane with chlorine using structural formulas and indicating all steps separately. How do radical reactions differ from most other reactions? c. Tuliskan mekanisme tindak balas penambahan air bermangkin asid kepada 2-metil-2-pentena, dan jelaskan kepilihan tindak balas ini. Write the reaction mechanism for the acid catalysed addition of water to 2- methyl-2-pentene, and explain the selectivity of the reaction. (15 markah / marks)

4 SCEP1252/04 4. Berikan formula struktur untuk semua hasil utama bagi tindak balas A, B, C dan D, dengan andaian tindak balas satu langkah sahaja. Provide the structural formulas for all major reaction product(s) of reactions A, B, C and D, assuming single reactions only. CH 3 (A) Cl 2 [AlCl 3 ] Cl 2 h (B) (C) F 2 Br 2 h (D) (5 markah / marks) BAHAGIA B (33 MARKAH) SECTIO B (33 MARKS) Jawab SOALA 5 DA 6 dan pilih MAA-MAA DUA DARI SOALA 7 dalam bahagian ini. Answer QUESTIOS 5 AD 6 and choose AY TWO FROM QUESTIO 7 in this section. 5. Tuliskan persamaan seimbang bagi setiap tindak balas berikut: Write a balanced equation for each of the following reactions: (a) Ca(OH) 2 (aq) + HCl(aq) CaCl 2 (aq) + H 2 O(l) (b) C 2 H 5 OH(g) + O 2 (g) CO 2 (g) + H 2 O(l) (c) Al 2 (SO 4 ) 3 (aq) + aoh(aq) Al(OH) 3 (s) + a 2 SO 4 (aq) (6 markah/ marks)

5 SCEP1252/05 6. Rujuk pada Jadual Berkala sahaja Refer only to the Periodic Table (i) (iii) Tentukan yang mana diantara Sc, Ba dan Se mempunyai atom paling besar. Jelaskan pilihan jawapan anda. Determine which is the largest atom amongst Sc, Ba and Se. Explain your choice. Susunkan spesies K +, Cl -, S 2-, and Ca 2+ dalam urutan meningkat saiznya. Jelaskan jawapan anda. Arrange the species K +, Cl -, S 2-, and Ca 2+ in order of increasing size. Explain your answer. Susunkan unsur-unsur K, Mg, dan S dalam urutan jangkaan meningkat tenaga pengionan pertamanya. Jelaskan jawapan anda. Arrange the elements K, Mg, and S in the expected order of increasing first ionization energy. Explain your answer. (11 markah/ marks) 7. Jawab 2 daripada soalan-soalan berikut: Solve any 2 of the following questions: (a) (i) Kalsium karbonat (CaCO 3 ) merupakan galian utama dalam batu kapur. Berapakah jisim dalam gram satu sampel 4.86 mol CaCO 3? Calcium carbonate (CaCO 3 ) is the principal mineral found in limestone. What is the mass in grams of a 4.86 moles sample of CaCO 3? Satu sampel larutan asid hidroklorik memerlukan ml larutan natrium hidroksida M bagi peneutralan. Berapakah kepekatan sampel asid hidroklorik asal? A ml sample of hydrochloric acid solution requires ml of M sodium hydroxide for complete neutralization. What is the concentration of the original hydrochloric acid solution? (b) Suatu serbuk putih dianalisis dan didapati mengandungi 43.64% fosforus dan 56.36% oksigen dari segi jisim. Sebatian mempunyai jisim molar g/mol. Apakah formula empirik dan formula molekul sebatian itu? A white powder is analyzed and found to contain 43.64% phosphorus and 56.36% oxygen by mass. The compound has a molar mass of g/mol. What are the compound s empirical and molecular formulas?

6 SCEP1252/06 (c) (i) Kirakan jisim pepejal acl yang perlu ditambahkan ke suatu larutan 1.50 L AgO 3 kepekatan M untuk memendakkan kesemua ion Ag + sebagai AgCl. Calculate the mass of solid acl that must be added to 1.50 L of a M AgO 3 solution to precipitate all the Ag + ions in the form of AgCl. Ramalkan apakah yang akan berlaku apabila pasangan larutan berikut dicampurkan. Predict what will happen when the following pairs of solutions are mixed. A. Larutan akues kalium hidroksida dicampurkan dengan larutan akues ferum(ii) nitrat. Aqueous potassium hydroxide is mixed with aqueous iron(iii) nitrate. B. Larutan akues natrium sulfat dicampurkan dengan larutan akues plumbum(ii) nitrat. Aqueous sodium sulphate is mixed with aqueous lead(ii) nitrate. (d) (i) Susu magnesia, yang merupakan ampaian akues magnesium hidroksida Mg(OH) 2 sering digunakan sebagai antasid. Ia meneutralkan asid hidroklorik berlebihan dalam perut menghasilkan magnesium klorida dan air. Kirakan bilangan mol HCl yang dineutralkan oleh 1.00 g Mg(OH) 2. Milk of magnesia, which is an aqueous suspension of magnesium hydroxide Mg(OH) 2, is often used as an antacid. It neutralizes excess hydrochloric acid secreted by the stomach to form magnesium chloride and water. Calculate the number of moles of HCl neutralized by 1.00 g of Mg(OH) 2. Hitungkan kemolaran satu larutan yang disediakan dengan melarutkan 11.5 g pepejal aoh dalam air secukupnya untuk menghasilkan 1.50 L larutan. Calculate the molarity of a solution prepared by dissolving 11.5 g of solid aoh in enough water to make 1.50 L of solution. (16 markah/ marks)

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8 SCEP1252/08 Jawab semua soalan di dalam bahagian ini. Answer all questions in this section. BAHAGIA C (34 MARKAH) SECTIO C (34 MARKS) 8. (a) Berikan takrifan untuk Hukum Pengabadian Jirim dan Hukum Berbilang Kadar. Give the definitions on Law of Conservation of Matter and Law of Multiple Proportions. (b) ZnCO 3 + H 2 SO 4 ZnSO 4 + CO 2 + H 2 O (2 markah/ marks) Daripada tindak balas kimia di atas, 50.0g ZnCO 3 dan 24.5g H 2 SO 4 bertindakbalas untuk membentuk ZnSO 4. Kirakan: For the chemical reaction above, 50.0g of ZnCO 3 and 24.5g H 2 SO 4 reacted to form ZnSO 4. Calculate: (i) (iii) jisim ZnSO 4 yang terbentuk. the mass of ZnSO 4 formed. bilangan molekul CO 2 yang terbebas. the number of molecules of CO 2 liberated. baki jisim ZnCO 3 selepas tindak balas. the remaining ZnCO 3 after reaction completed. (JAR Zn: 65, C: 12, O: 16, H: 1, S: 32, A = 6.02 x ). (RAM Zn: 65, C: 12, O: 16, H: 1, S: 32, A = 6.02 x ). (4 markah/ marks) (c) Dengan bantuan gambarajah, jelaskan mengapa zarah alpha, beta and gamma menunjukkan pergerakkan yang berlainan di bawah medan elektrik? With the help of a diagram, describe why the alpha, beta and gamma particles deflecting differently under an electric field? (4 markah/ marks)

9 SCEP1252/09 9. (a) Berikan postulat eils Bohr ke atas model atom dan jelaskan jawapan anda dengan bantuan gambarajah. Apakah perubahan tenaga apabila satu elektron dalam atom hidrogen berubah petala dari paras teruja kedua (n = 3) ke paras tenaga dasar. Apakah jarak gelombang untuk sinaran yang terpancar itu? (h = 6.63 x Js, c = 3 x 10 8 ms -1, R H = 2.18 x J) Write down the eils Bohr s postulate for atomic model, and illustrate your answer with the aids of a diagram. What is the energy change when the electron in a hydrogen atom transits from the second excited state (n = 3) to the ground state? What is the wavelength of the radiation emitted? (h = 6.63 x Js, c = 3 x 10 8 ms -1, R H = 2.18 x J) (6 markah/ marks) (b) Apakah ketiga-tiga prinsip utama untuk konfigurasi elektronik suatu atom? Berikan konfigurasi elektron dan lukis gambarajah orbital tahap tenaga dasar untuk atom kalium (K, Z = 19). What are the three main principles to follow for an electronic configuration of an atom? Give the electronic configuration and draw the ground-state orbital energy level diagram for potassium atom (K, Z = 19). (6 markah/ marks) 10. (a) Terbitkan Persamaan Gas Unggul daripada hukum gas unggul. Berikan juga formula untuk Faktor Kemampatan Gas, Z. Apakah nilai Z untuk gas unggul? Derive the Perfect Gas Equation from perfect gas laws. Give the formula for Compression Factor of gases, Z. What is the value of Z for a perfect gas? (5 markah/ marks) (b) Senaraikan tiga andaian untuk Teori Kinetik Gas. Give the three assumptions of Kinetic Theory of Gases. (3 markah/ marks) (c) Dalam suatu proses industri, gas nitrogen pada asalnya mempunyai tekanan 100 atm dan suhu 300 K. Apakah tekanannya apabila gas tersebut dipanaskan sehingga 600 K, anggapkan ia bersifat seperti gas sempurna? Dan apakah suhu akhir sekiranya tekanan gas dinaikkan ke 300 atm? In an industrial process, nitrogen gas enters the vessel initially at a pressure of 100 atm and a temperature of 300 K. What pressure would it exert when the gas is heated to 600 K, assuming the gas behaves ideally? And what would be the temperature if the pressure of the gas is increased to 300 atm? (4 markah/ marks) TAMAT ED