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Chemistry Grade 12 Unit 5: INTRODUCTION TO ENVIRONMENTAL CHEMISTRY

national exam questions have come from this unit. It runs 50 pages; one careful study pass takes about 4.5 hours, and its difficulty is harder among Chemistry units. Each section below lists the questions set from it, with the year, and opens the page that teaches it.

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5.1 Introduction · read p. 241
Not asked in a national paper yet.
5.1.1 Components of the Environment · read p. 241
  • 2016 E.C., Q66 – The component of the environment consisting earth's upper outer most skin, and accessible to human beings is known as _____.
5.1.2 Natural Cycles in the Environment · read p. 247
  • 2018 E.C., Q71 – Which one of the following reactions creates energy in our bodies during respiration?
  • 2016 E.C., Q67 – Consider the following steps that occur during the nitrogen cycle: Step: 1 Reduction of nitrate by microbial action Step: 2 Fixation of nitrogen by bacteria and algae Step: 3 Nitrification by nitrososnas and nitrobactra
  • 2015 E.C., Q60 – Which one of the following reactions creates energy in our bodies during respiration?
  • 2013 E.C., Q8 – CO 2 is released into the atmosphere by one of the following processes
  • 2011 E.C., Q13 – What makes the phosphorus cycle different from the carbon and nitrogen cycles?
  • 2009 E.C., Q57 – In what way is the phosphorous cycle differs from the carbon and nitrogen cycle?
5.1.3 Concepts Related to Environmental Chemistry · read p. 253
Not asked in a national paper yet.
5.2 Environmental Pollution · read p. 255
Not asked in a national paper yet.
5.2.1 Air Pollution · read p. 256
  • 2017 E.C., Q15 – Which of the following is NOT true about greenhouse effect and greenhouse gases?
  • 2016 E.C., Q68 – Some hazardous substances damage and create unwanted changes in air, water, soil or any other natural resource. The resulting change created is known as:
  • 2015 E.C., Q28 – Which one of the following gases is released from combustion of a fuel in an industrial machinery causing global warming?
  • 2014 E.C., Q16 – How can a project of establishing an industry that consumes coal affect the environment?
5.2.2 Water Pollution · read p. 260
  • 2018 E.C., Q65 – Which of the following is NOT a method of reducing water pollution?
5.2.3 Land Pollution · read p. 262
  • 2017 E.C., Q19 – What is the name given to the pollution caused by the dumping of non-biodegradable wastes into the environment?
5.3 Global Warming and Climate Change · read p. 265
Not asked in a national paper yet.
5.3.1 Global Warming and Climate Change · read p. 265
Not asked in a national paper yet.
5.3.2 Chemistry of Greenhouse Gasses and Their Effects on Climate Change · read p. 267
  • 2018 E.C., Q72 – The following gases contribute to the greenhouse effect on Earth. Which is the correct order of their importance from greatest to smallest?
5.4 Green Chemistry and Cleaner Production · read p. 269
Not asked in a national paper yet.
5.4.1 Principle of Green Chemistry · read p. 271
Not asked in a national paper yet.
5.4.2 Cleaner Production in Chemistry · read p. 277
  • 2018 E.C., Q75 – The following reaction can be used for the synthesis of CH₃CH=CHCH₃ as a desired product: CH₃CH₂CHBrCH₃ + CH₃S⁻ → CH₃CH=CHCH₃ + CH₃SH + Br⁻. What is the atom economy for the above reaction?
  • 2017 E.C., Q60 – The following reaction can be used for the synthesis of CH CH CH CH as a desired product: CH CH CHBrCH 3 2 2 3 3 2 3 3 − 3 − + CH S → CH CH CH CH + CH SH + Br Which of the following is the atom economy for the above 3 2