UNIVERSITI MALAYA UNIVERSITY OF MALAYA PEPERIKSAAN IJAZAH SARJANA MUDA SAINS EXAMINATION FOR THE DEGREE OF BACHELOR OF SCIENCE PEPERIKSAAN IJAZAH SARJANA MUDA SAINS DENGAN PENDIDIKAN EXAMINATION FOR THE DEGREE OF BACHELOR OF SCIENCE WITH EDUCATION SESI AKADEMIK 2015/2016 : SEMESTER I ACADEMIC SESSION 2015/2016 : SEMESTER I SCES1200/ SIC1001/ SIX1009 : PRINSIP-PRINSIP KIMIA/ PRINSIP KIMIA / KIMIA AM PRINCIPLES OF CHEMISTRY/ PRINCIPLE OF CHEMISTRY/ GENERAL CHEMISTRY Jun 2016 June 2016 Masa: 2 jam Time: 2 hours ARAHAN KEPADA CALON INSTRUCTIONS TO CANDIDATES : Kertas soalan ini mengandungi Bahagian A dan B. This paper consists of Section A and B. 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 8 halaman yang dicetak) (This question paper consists of 10 questions on 8 printed pages)
BAHAGIAN A (50 MARKAH) SECTION A (50 MARKS) Jawab SEMUA soalan Answer ALL questions 1. (a) Adakah teori atom oleh Democritus masih relevan pada hari ini? Beri pendapat anda. Are Democritus theories of atoms still relevant today? Give your opinion. (c) Terangkan tiga prinsip yang menjadi panduan kepada konfigurasi elektron bagi atom. Explain three principles that guide the electron configuration of an atom. Tulis persamaan Schrondinger dan ulas persamaan tersebut. Write the equation of Schrondinger and particularize the equation. 2. (a) Jelaskan maksud jisim hitam dan malapetaka ultraviolet. Define blackbody and ultraviolet catastrophe. (12 markah/marks) (c) Apakah idea-idea Planck bagi memperbetulkan idea fizik klasik. What are the ideas that Planck suggested to correct the classical physics? Graf menunjukkan bagaimana lengkung radiasi jasad hitam berubah pada suhu berbeza. Ulas graf tersebut. The graph shows how the black body radiation curves change at various temperatures. Explain the graph. 2/8
3. Pada 1909, Robert A. Millikan telah melakukan satu eksperimen yang dinamakan Eksperimen Titis Minyak untuk menentukan caj bagi satu electron. Perincikan eksperimen itu dan penemuannya. In 1909 Robert A. Millikan came up with an experiment to measure the charge on an electron, called the Oil Drop Experiment. Describe the experiment and its finding. (8 markah/marks) 4. (a) Bagaimana tekanan udara di dalam satu belon berubah apabila belon itu ditekan? Terangkan apakah yang berlaku menggunakan hukum gas. How does the air pressure in a balloon change when the balloon is squeezed? Explain why this change occurs using gas laws. Pada suhu 15 o C, 25 ml neon pada tekanan 101.3 kpa (1 atm) dan 75 ml helium pada tekanan 70.9 kpa (0.7 atm) mengembang di dalam bekas tertutup rapat yang berisipadu 1 L. Kirakan tekanan separa bagi setiap gas dan jumlah tekanan bagi campuran gas. At 15 o C, 25 ml of neon at 101.3 kpa (1 atm) and 75 ml of helium at 70.9 kpa (0.7 atm) are both expanded into a 1 L sealed flask. Calculate the partial pressure of each gas and the total pressure of the gas mixture. 3/8
5. (a) Dengan menggunkan persamaan Van der Waals, kirakan suhu 20.0 mol helium di dalam silinder berisipadu 10.0 liter pada 120 tekanan atmosfera. Using Van der Waals equation, calculate the temperature of 20.0 mole of helium in a 10.0 litre cylinder at 120 atmosphere pressure. [Data - Van der Waals constants for helium: a = 0.0341 L 2 at mol -2 ; b = 0.0237 L mol -1, R = 8.314 JK -1 mol, R = 0.082 L atm K -1 mol -1 ] (c) Bandingkan nilai tersebut dengan suhu yang dikira menggunakan persamaan gas ideal. Compare this value with the temperature calculated from the ideal gas equation. Molekul manakah di antara O 2 dan N 2 yang bergerak lebih pantas pada suhu yang sama? Berapa banyakkah perbandingan kelajuan tersebut? Which molecule between O 2 and N 2 travels faster at the same temperature? How much faster? 4/8
BAHAGIAN B (50 MARKAH) SECTION B (50 MARKS) Jawab SEMUA soalan Answer ALL questions 6. (a) Apakah formula empirik? What is empirical formula? Sebatian adrenalina akan terembes di dalam badan manusia apabila berlaku tekanan; ianya menaikkan kadar metabolism badan. Seperti kebanyakan sebatian di dalam sistem kehidupan, ia mengandungi karbon, hidrogen, oksigen, dan nitrogen. Melalui eksperimen, ia didapati mengandungi 56.8% C, 6.50% H, 28.4% O, and 8.28% N. Apakah formula empirik adrenalina? The compound adrenaline is released in the human body in times of stress; it increases the body s metabolic rate. Like many compounds in living systems, it is composed of carbon, hydrogen, oxygen, and nitrogen. It was found by experiment to have the composition 56.8% C, 6.50% H, 28.4% O, and 8.28% N. What is the empirical formula of adrenaline? [Jisim atom/atomic mass: C = 12.0; H = 1.0; N = 14.0; O = 16.0] Boron oksida kontang, B 2 O 3 (p), bertindak balas dengan serbuk magnesium apabila dipanaskan dengan kuat untuk menghasilkan magnesium oksida, MgO(p), dan magnesium borida, Mg 3 B 2 (p). Tuliskan persamaan seimbang untuk tindak balas ini. Dry boron oxide, B 2 O 3 (s), reacts on strongly heating with magnesium powder on strong heating to give a mixture of magnesium oxide, MgO(s), and magnesium boride, Mg 3 B 2 (s). Write a balanced equation for the reaction. Magnesium borida bertindak balas dengan larutan akueus asik hidroklorik, HCl(ak), menghasilkan suatu hidrida boron dengan formula B 4 H 10, MgCl 2, dan H 2. Apakah hasil maksimum B 4 H 10 yang mungkin dihasilkan daripada 10.00 g B 2 O 3? Magnesium boride reacts with dilute aqueous hydrochloric acid, HCl(aq), to give a hydride of boron of formula B 4 H 10, MgCl 2, and H 2. What is the maximum possible yield of B 4 H 10 from 10.00 g B 2 O 3? [Jisim atom/atomic mass: B = 10.8; O = 16.0; H = 1.0; Cl = 35.5; Mg = 24.0] 5/8
7. (a) Jelaskan makna hasilan teori, hasilan sebenar dan peratus hasilan di dalam sesuatu tindak balas. Explain the meanings of theoretical, actual and percent yields in a reaction. Tindak balas di antara 15.0 g C 4 H 9 OH, 22.4 g NaBr, dan 32.7 g H 2 SO 4 menghasilkan 17.1 g C 4 H 9 Br di dalam tindak balas berikut: Apakah: What are: The reaction of 15.0 g C 4 H 9 OH, 22.4 g NaBr, and 32.7 g H 2 SO 4 yields 17.1 g C 4 H 9 Br in the following reaction: C 4 H 9 OH + NaBr + H 2 SO 4 C 4 H 9 Br + NaHSO 4 + H 2 O (i) (ii) hasilan teori; the theoretical yield; peratus hasilan C 4 H 9 Br di dalam tindak balas ini? the percent yield of C 4 H 9 Br of this reaction. [Jisim atom/atomic mass: C = 12.0; H = 1.0; Na = 23.0; Br = 80.0; O = 16.0; S = 32.0] 8. (a) Satu botol asid sulfurik pekat mempunyai label berikut: A bottle of concentrated sulphuric acid has the following labels: 98.0% H 2 SO 4 mengikut jisim dan ketumpatan 1.84 g cm -3 98.0% H 2 SO 4 by mass and density of 1.84 g cm -3 (i) Apakah kemolaran asid pekat ini? What is the molarity of the concentrated acid? (ii) Berapakan isipadu asid pekat ini yang diperlukan untuk menghasilkan 10.0 L larutan 0.200 M H 2 SO 4? What volume of this concentrated acid is required to make 10.0 L of 0.200 M H 2 SO 4 solution? 6/8
50.0 cm 3 larutan 0.400 M asid hidroklorik dicampurkan kepada 25.0 cm 3 larutan natrium hidroksida dan larutan yang terhasil memerlukan 21.6 cm 3 larutan 0.200 M natrium hidroksida untuk peneutralan. Hitung kepekatan larutan natrium hidroksida asal. 50.0 cm 3 of a 0.400 M hydrochloric acid solution was added to 25.0 cm 3 of a solution of sodium hydroxide and the resulting solution required 21.6 cm 3 of 0.200 M sodium hydroxide solution for neutralisation. Calculate the concentration of the original sodium hydroxide solution. [Jisim atom/atomic mass: H = 1.0; O = 16.0; S = 32.0; Na = 23.0] 9. (a) Dengan menggunakan atom/ion Ca (Z = 20) dan F (Z = 9) sebagai contoh, tunjukkan bagaimana suatu ikatan ion terbentuk. By using atom/ion of Ca (Z = 20) and F (Z = 9) as examples, show how an ionic bond is formed. Lukiskan struktur Lewis lengkap untuk ion sulfit, SO 3 2- ; Draw a complete Lewis structure for sulphite ion, SO 3 2- ; (i) (ii) Ramalkan bentuk atau geometrinya; Predict its geometry or shape; Apakah penghibridan yang mungkin pada atom pusat anion ini? What is the possible hybridisation at the central atom of this anion? 10. (a) Bagaimana saiz atom berubah dari kiri ke kanan sesuatu kala, dan apabila menuruni sesuatu kumpulan dalam jadual berkala? Apakah sebab kepada semua perubahan ini? How does the size of atoms vary from left to right in a period, and on descending a group in the periodic table? What are the reasons for these changes? (c) Jelaskan gas lengai/nadir mempunyai jejari atom yang besar. Explain why noble gases have large atomic radii. Kenapa pengurangan saiz di antara Li (152 pm) dan Be (111 pm) lebih besar jika dibandingkan dengan Na (186 pm) dan Mg (160 pm)? Why is the decrease in size between Li (152 pm) and Be (111 pm) much greater than that between Na (186 pm) and Mg (160 pm)? 7/8
(d) Kenapa ion-ion O 2-, F -, Na +, dan Mg 2+ di rujuk sebagai siri ion isoelektron? Why are the ions O 2-, F -, Na +, and Mg 2+ referred to as an isoelectronic series of ions? (e) Jelaskan penurunan dalam jejari ion pada siri ion berikut: Explain the decrease in ionic radius in the following series of ions: O 2- (140 pm) > F - (135 pm) > Na + (102 pm) > Mg 2+ (72 pm) [Nombor atom/atomic Number: Li = 3, Be = 4; O = 8; F = 9; Na = 11; Mg = 12] TAMAT END 8/8