⚗️ Chemical Engineering Solved MCQs with Answers

Practice 1920 approved ⚗️ Chemical Engineering questions with verified answers from the 🛠️ Engineering Essentials subject for Pakistan exams.

1920 solved MCQs

The permissible color for domestic water supply is __________ ppm.Answer: 20 High noise levels produced during operation of fans and compressors can be reduced by usingAnswer: Mufflers (silencers). The Killer gas which caused Bhopal gas tragedy in 1984 wasAnswer: Phosgene Aerosols present in atmospheric air may beAnswer: Combination of all (a), (b) & (c). Ethanolamine is an absorbant used for the removal of __________ from air/gas.Answer: Both (b) & (c) Which of the following causes death by asphyxiation, if its presence in atmospheric air exceeds maximum allowable concentration (i.e. > 50 ppm) ?Answer: Carbon monoxide __________ plant emits large amount of SO₂ as an air pollutant.Answer: Sulphuric acid Noise pollution level in a chemical plant is expressed inAnswer: Decibel The maximum permissible noise level to which a man working in a chemical plant can be exposed for eight hours per day is about __________ decibels.Answer: 90 The most commonly used chemical coagulant in water treatment isAnswer: Alum The biological decomposition of organic substances in wastes controlled conditions is calledAnswer: Composting Lung cancer & DNA breakage are the major ill effects of excessive ozone exposure to human beings. Ozone layer depletion in the atmosphere is mainly caused by the presence ofAnswer: CFC (chloro fluoro carbon) Smog is not formed due to the presence of __________ in the atmosphere.Answer: CO₂ Pick out the correct statement.Answer: Global warming is detrimental for increase in food productivity and may cause flood and cyclone. Which of the following is not a source of ozone emission in the atmosphere ?Answer: Refrigerators. Oceans act as sinks for atmospheric gases including carbon dioxide whose concentration in the atmosphere is increased by theAnswer: Green house effect Pick out the correct statement.Answer: All (a), (b) and (c). The upper layer of atmosphere is called theAnswer: Stratosphere Which of the following is the most widely used disinfectant in water treatment ?Answer: Chlorine Pick out the wrong statementAnswer: Both (b) and (c). Phenolic water generated in coke ovens & by-product plant of a steel plant are disposed off byAnswer: Quenching of hot coke. 5-200 μm size particles are calledAnswer: Colloids or aerosols The progressive warming up of the earth's surface is mainly due to theAnswer: Blanketing effect of CO₂ in the atmosphere. The effect of increase in carbon dioxide level of the atmosphere and its profound effect on our climate is called theAnswer: Both (b) and (c) Arsenic pollutant is not generated in____industries.Answer: Beverages The resistance of water to the passage of light through it is a measure of theAnswer: Turbidity Color test of water is done with an instrument calledAnswer: Tintometer Which of the following gases is having the widest explosion limit (about 2 to 81% gas in gas-air mixture), rendering it the property of the most explosive gas ?Answer: Acetylene Pick out the wrong statement pertaining to 'green house' for the plants.Answer: 'Green house' is colder than the outside atmosphere. In water treatment, alum[Al₂(SO₄)₃] is used for the process ofAnswer: Coagulation