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 2 ACADEMIC SESSION 2015/2016 : SEMESTER 2 SCES2243 : KIMIA ALAM SEKITAR AM GENERAL ENVIRONMENTAL CHEMISTRY Jun 2016 June 2016 Masa : 2 jam Time : 2 hours ARAHAN KEPADA CALON : INSTRUCTIONS TO CANDIDATES: Kertas soalan ini mengandungi Bahagian A dan 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 11 soalan dalam 7 halaman yang dicetak) (This question paper consists of 11 questions on 7 printed pages)
Jawab semua soalan daripada Bahagian ini Answer all questions from this Section BAHAGIAN A (50 MARKAH) SECTION A (50 MARKS) 1. (a) Terangkan mengapa suhu berkurangan bersama altitud dalam troposfera? Explain why the temperature decreases with altitude in the troposphere? Terangkan mengapa suhu meningkat bersama altitud dalam stratosfera. Explain why the temperature increases with altitude in the stratosphere. 2. (a) Masa menghuni wap air di kawasan tropika ialah ~ 5 hari, tetapi di kawasan kutub ianya ~ 12 hari. Terangkan mengapa. The residence time of water vapour in the tropics is ~ 5 days but in the polar region it is ~ 12 days. Explain why. Ahli kimia atmosfera yang terkenal, iaitu C.E. Junge telah membuat suatu pemerhatian yang penting berkenaan dengan masa menghuni dan keberubahan gas-gas di atmosfera. Apakah pemerhatian tersebut? The famous atmospheric chemist C.E. Junge made an important observation about residence times and the variability of gases in the atmosphere. What was the observation? 3. (a) Terangkan maksud setiap sebutan berikut: Explain the meaning of each of the following terms: (i) (ii) Penetapan nitrogen Nitrogen fixation Ammonifikasi Ammonification 2/7
(iii) (iv) Nitrifikasi Nitrification Denitrifikasi Denitrification (6 markah/marks) 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? (4 markah/marks) 4. (a) Lukiskan struktur hasil pertama yang terbentuk daripada tindak balas sebatian berikut dengan radikal hidroksil (OH ) Draw the structure of the first product formed from the reaction of the following substances with the hydroxyl radical (HO ). (i) (ii) (iii) (iv) CH 3 CH 2 CH=CH 2 + HO CH 3 CH 2 C(=O)H + HO CH 3 CH 2 CH 2 CH 2 CH 3 + HO NO 2 + HO Apakah cirri-ciri bagi H 2 O dan CO 2 yang menyebabkan molekul-molekul tersebut menyerap sinaran infra-merah? What characteristics of H 2 O and CO 2 molecules that cause their absorption of infrared radiation? 5. (a) Tuliskan persamaan-persamaan yang bersesuaian bagi menggambarkan proses bermangkin yang memusnahkan ozon di stratosfera sebelah bawah. Write down the appropriate equations by which ozone destruction occurs in the lower stratosphere by a catalytic process. (6 markah/marks) 3/7
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 (4 markah/marks) 4/7
BAHAGIAN B (50 MARKAH) SECTION B (50 MARKS) Jawap SEMUA soalan daripada Bahagian ini. Answer ALL questions from this Section. 6. Apa itu bahan humus? Bincangkan bagaimana bahan humus mempengaruhi kepekatan logam dalam air. What is humic substances? Discuss how humic substances influence the concentration of metals in water. (10 markah/marks) 7. Apakah maksud kealkalian? Berdasarkan gambarajah di bawah, terangkan bagaimana kealkalian mengekalkan ph air What is alkalinity? Based on the following figure, discuss how alkalinity maintained the water ph in nature. 8. Terangkan secara ringkas proses rawatan kumbahan primer dan sekunder. Briefly explain the process of primary and secondary treatment in sewage treatment. (10 markah/marks) 5/7
9. (a) Terangkan bagaimana baja yang mengandungi fosforus (P), nitrogen (N) dan kalium (K) meningkatkan kesuburan tanah. Discuss how the fertilizer containing phosphorus (P), nitrogen (N) and potassium (K) improves the fertility of soils. (5markah/marks) Tanah kehilangan nutrien seperti ion ammonium (NH 4 + ), kalium (K + ), magnesium (Mg 2+ ) and kalsium (Ca 2+ ) melalui proses larut lesap. Terangkan. Soils may loss its nutrient such as ammonium (NH 4 + ), potassium (K + ), magnesium (Mg 2+ ) and calcium (Ca 2+ ) ion through leaching. Explain. (10 markah/marks) 10. (a) Apakah yang dimaksudkan dengan keupayaan pertukaran kation (CEC)? What is cation exchange capacity (CEC)? (2 markah/marks) 1.00 g tanah diekstrakkan dengan 100 ml laruatan ammonium klorida untuk menggantikan kation yang terkandung dalam tanah. Jumlah caj positif untuk ion Ca 2+, Mg 2+, K +, Na + and H + adalah seperti yang disenaraikan dalam jadual berikut. Kira ketepuan bes (%) bagi sampel tanah ini. 1.00 g of soil was extracted with 100 ml of the ammonium chloride solution in order to displace the cations from the soils. The total positive charge associated with Ca 2+, Mg 2+, K +, Na + and H + ion is listed in the following table. Calculate the base saturation (%) of this soil sample. Ion Jumlah caj positif / Total positive charge (cmol (+) kg -1 ) Ca 2+ 15.0 Mg 2+ 2.5 K + 0.5 Na + 0.1 H + 26.0 (3 markah/marks) 6/7
11. Terangkan proses pembentukan cecair larut lesap dari tanah timbus. Mengapakah pembentukan cecair larut lesap merupakan masalah utama bagi pengurusan sisa buangan campuran? Describe the process of landfill leachate formation. Why leachate formation is the major problem for mixed urban waste management? TAMAT END 7/7