ENGR 202 Midterm Exam | Complete Questions and Answers | Winter 2025/2026 - Concordia University.

ENGR 202 Midterm Exam | Complete Questions and Answers | Winter 2025/2026 - Concordia University. Sustainable Development and Environmental Stewardship (ENGR 202) Midterm Exam – Winter 2025 1. The gas composition of the emissions of a factory is measured and listed in the table below. Assuming that the overall flowrate of the gas stream is 55000 kg per year, calculate the total GHG-100 emissions of the plant in kg CO2,eq per year (10 points). Component CH4 CO2 N2O HFC-23 HFC-41 Mass% 7 85 3 3 2 The global warming potential of different gases is shown in the following table. Component Global warming potential, time horizon 20 years 100 years 500 years CO2 1 1 1 CH4 56 21 6.5 N2O 280 310 170 HFC-23 9100 11700 9800 HFC-41 490 150 45 2. Methane is classified as one of the key greenhouse gases with a relatively long decay period. Assuming 10 kg of methane is released into the atmosphere, and after 31 years 87% of that breaks down into water and CO2, determine the half-life of methane (10 points). 3. Which pollutants are identified as the six Criteria Air Pollutants? (6 points) 4. Explain the difference between weather and climate change (4 points) 5. Explain resilience in the context of the environment (3 points) 6. What gas is beneficial in the stratosphere but causes damage to plants and animals in the troposphere? Explain how it is typically formed in the troposphere. (6 points) 7. Name one oil-related environmental disaster and give its approximate location (4 points) 8. Calculate the mass flowrates of F1, F2, and waste streams for a chemical plant with the following conditions. Assume that this plant produces 100 kg/h Product and the waste stream contains no C and 5 kg/h of B. (15 points) F1 (0.5 A, 0.5 B) F2 (0.1A, 0.9C) Recycle Waste Product (0.1C, 0.9B) 9. A team of engineers is called to a site in Canada where the water seems to be turning green and cloudy. A water sample shows that the concentration of algae is much higher than expected. (10 points) a. What environmental problem is likely occurring here? b. Explain the cause-and-effect chain of this problem c. What consequences are likely to occur if action is not taken? d. What would you expect to find in the surrounding areas that could be causing this? e. What federal legislation would be most relevant in this case? 10. A 10 mL water sample is taken to a laboratory, and diluted to 100 mL with water having 20 mg/L dissolved oxygen. Before an incubation period of five days, the diluted sample has dissolved oxygen of 19 mg/L and afterward is measured to have 5 mg/L. The dilution water is measured to have dissolved oxygen of 18.5 mg/L after five days. What is the BOD5 of the sample? (8 points) 11. (8 points) What are the categories for radioactive waste? How would you classify: a. Mixed rock and metals from the purification of uranium ore b. A 12g piece of Plutonium c. Clothes worn by a worker in a nuclear power station d. Fuel rods that leave the nuclear reaction vessel 12. Describe the effect of carbon dioxide and methane in terms of the energy balance of the planet (6 points) 13. How is the concentration of fecal coliform bacteria used when doing water quality testing? What are the tests trying to determine? (4 points) 14. A family goes on a camping trip and cooks their meals over a wood fire. (6 points) f. Should they be concerned about the climate change impact of this activity? g. If the family returns to the city and is choosing between having a wood fire in a city park or cooking at home using a natural gas stove, what environmental impacts should they consider?