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 2013/2014 : SEMESTER 1 ACADEMIC SESSION 2013/2014 : SEMESTER 1 : KIMIA ALAM SEKITAR AM GENERAL ENVIRONMENTAL CHEMISTRY Disember 2013/Januari 2014 December 2013/January 2014 MASA : 2 jam TIME : 2 hours ARAHAN KEPADA CALON : INSTRUCTIONS TO CANDIDATES: Kertas soalan ini mengandungi Bahagian A and Bahagian B. This question paper consists of Section A and Section B. Jawab soalan mengikut arahan yang diberikan dalam setiap bahagian. Answer the questions according to the instructions given in each section. (Kertas soalan ini mengandungi 10 soalan dalam 5 halaman yang dicetak) (This question paper consists of 10 questions on 5 printed pages)
BAHAGIAN A (50 MARKAH) SECTION A (50 MARKS) Jawab mana-mana LIMA (5) soalan daripada Seksyen ini Answer any FIVE (5) questions from this Section 1. Terangkan bagaimana hubungan masa menghuni sesuatu spesis kimia dengan kereaktifan, kepekatan dan taburan spesis tersebut di atmosfera. Explain the relationship between atmospheric residence time of a chemical species with its reactivity,concentration and distribution in the atmosphere. 2. Terangkan maksud setiap sebutan berikut: Explain the meaning of each of the following terms: (i) (ii) (iii) (iv) Penetapan nitrogen Nitrogen fixation Ammonifikasi Ammonification Nitrifikasi Nitrification Denitrifikasi Denitrification 3. (a) Terangkan mengapa NO tidak mengurai kepada N 2 setelah terbentuk daripada tindakbalas di antara N 2 dan O 2. Gunakan gambarajah profil tenaga dalam jawapan anda. Explain why NO will not dissociate into N 2 and O 2 once formed from the reaction of N 2 with O 2. Use the energy profile diagrams in your explanation. Terangkan mengapa molekul oksigen dalam keadaan triplet lebih stabil di sekitaran berbanding keadaan singlet? Expain why oxygen molecules in the triplet state are more stable in the environment than those in the singlet state? 2/5
4. Tuliskan persamaan-persamaan bagi menunjukkan tindak balas di mana karbon monoksida dioksidakan kepada karbon dioksida, bermula dengan tindak balas dengan radikal hidroksil, OH. Kemudian, dengan menambahkan proses di mana HOO ditukarkan kembali kepada HO, deduksikan persamaan keseluruhannya. Write equations showing the reactions by which atmospheric carbon monoxide is oxidized to carbon dioxide, starting by first reacting with hydroxyl radical, HO. Then, by adding the process by which HOO is returned to OH, deduce the overall reaction. [ Diberi/Given: HOO + NO HO + NO 2 ] 5. (a) Huraikan kesan penipisan lapisan ozon stratosfera ke atas alam sekitar. Describe the effects of the depletion of stratospheric ozone layer on the environment Huraikan kesan pemanasan global ke atas alam sekitar. Describe the effects of global warming on the environment 6. (a) Hitungkan ph air hujan yang berada pada kesimbangan dengan SO 2 dalam jisim udara tercemar di mana nisbah percampuran sulfur dioksida adalam 1.00 ppmv. Calculate the ph of rainwater in equilibrium with SO 2 in a polluted air mass for which the mixing ratio of sulphur dioxide is 1.00 ppmv. [Diberi/Given: K H = 1.0 M atm -1 ] Huraikan kesan hujan asid ke atas (a) aras aluminium terlarut, dan populasi ikan. Describe the effects of acid rain on (a) dissolved levels of aluminium, and fish populations. 3/5
7. Nyatakan jenis pencemar yang boleh dikeluarkan dengan menggunakan kaedah kawalan pencemaran udara berikut: State the types of atmospheric pollutants that may be removed by the following air pollution control methods: (i) (ii) (iii) (iv) Pengendapan graviti Gravity settling Penukar bermangkin Catalytic converter Penyentalan Scrubbing Pembakaran fluidized-bed Fluidized-bed combustion BAHAGIAN B (50 MARKAH) SECTION B (50 MARKS) Answer ALL questions from this Section. Jawab SEMUA soalan daripada Bahagian ini. 8. (a) Penukaran kation merupakan salah satu ciri tanah. Bincangkan. Cation exchange is one of the properties of soil. Discuss. (7 markah/marks) Bincangkan sifat-sifat bagi tanah terjejas oleh garam. Discuss the characteristics of the salt affected soils. (5markah/marks) (c) Logam wujud dalam pelbagai bentuk di dalam tanah. Bincangkan. Metal are present in a variety of forms in the soil. Discuss. (8 markah/marks) 4/5
9. (a) Apakah proses pengkompositan. What is compositing process? (5markah/marks) Larut lesapan daripada tapak pelupusan sampah biasanya mengandungi asid organik dan logam. Terangkan. Leachate from landfills usually contains organic acids and metal ions. Explain. 10. (a) Berdasarkan maklumat yang diberikan dalam jadual di bawah, bincangkan faktor-faktor yang mempengaruhi perbezaan kandungan pepejal terlarut dan nisbah Na/(Na + Ca) di dalam air sungai berikut: Based on the information given in the table below, discuss the factors that affect the differences in dissolved solid content and ratio of Na/(Na + Ca) in the following river waters: Sungai River Sungai Negro Negro River Sungai Jordan Jordan River Jumlah pepejal terlarut (mg/l) Total dissolved solid (mg/l) Nisbah Na/(Na+Ca) Ratio Na/(Na+Ca) < 20 0.9 >250 0.8 Sungai di kawasan batuan kapur mendapat kesan yang kurang daripada hujan asid berbanding sungai di kawasan granit. Terangkan. Rivers in limestone areas are less affected by acid rain compared to rivers in granite areas. Explain? (4 markah/marks) (c) Bincangkan tiga ciri-ciri utama air laut. Discuss three main characteristics of seawater. (6 markah/marks) TAMAT END 5/5