⚗️ 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

Operating principle of cyclone separator is based on the action of __________ dust particles.Answer: Centrifugal force on Exposure to small amount of __________ results in high blood pressure & heart disease in human beings.Answer: Cadmium Maximum allowable concentration of CO₂in air for safe working is __________ ppm (parts per million).Answer: 5000 Tolerable limit of nitrogen oxides in air is __________ ppm.Answer: 5 Iron & manganese present as pollutant in water can not be removed byAnswer: Chlorination. In water chemical treatment plant, use of chloramines ensuresAnswer: Disinfection. Which of the following is the common pollutant emitted from metallurgical smelters, thermal power plant and cement plants ?Answer: SO₂ During which of the following operating conditions of an automobile, carbon monoxide content in the exhaust gas is maximum ?Answer: Idle running During which of the following operating conditions of an automobile, carbon monoxide content in the exhaust gas is maximum ?Answer: Idle running H₂S present in gaseous stream can be removed by adsorption onAnswer: bog iron Inhalation of lead compounds present in automobile exhaust (using leaded petrol) causesAnswer: All (a), (b) & (c). Replenishment of dissolved oxygen in water stream polluted with industrial waste occurs byAnswer: Both (a) & (b). Aerodynamic noise resulting from turbulent gas flow is the most prevalent source of valve noise in fluid ilow control. It is caused due toAnswer: Both (a) & (b) Smoke is produced due toAnswer: All (a), (b) and (c). Fluorosis (a bone disease) is caused by the presence of high concentration of __________ in atmospheric air.Answer: Hydrogen flouride Threshold Limit Value (TLV) is the maximum allowable concentration (i.e. safe limit) of pollutants in air. Safe limit for SO₂ in air is __________ ppm.Answer: 5 Main pollutants released from iron & steel industry isAnswer: CO, CO₂ & SO₂. Exposure to chemicals having carcinogenic properties causeAnswer: Cancer Scale formation in boiler is controlled byAnswer: Reduction in hardness, silica & alumina in feed water. Noise level heard at a distance of about 100 metres from a jet engine with after burner is about __________ decibels.Answer: 170 TLV of mercury in potable (drinking) water is about __________ ppm.Answer: 0.001 Which is the best and the most effective method for the removal of organic contaminant present in the polluted water in very small quantity (say < 200 mg/litre)?Answer: Activated carbon adsorption Which is a secondary air pollutant ?Answer: Photochemical smog Which of the following is the most detrimental for water used in high pressure boiler ?Answer: Silica Turbidity of water is an indication of the presence ofAnswer: Suspended inorganic matter Presence of excess flourine in water causesAnswer: Fluorosis Siderosis is a disease caused by the inhalation of __________ dust.Answer: Iron Which of the following pollutants is not emitted during volcanic eruptions ?Answer: hydrocarbons The main pollutant in waste water discharged from a petroleum refinery is oil (both in free and emulsified form). Free oil is removed byAnswer: Gravity separator having oil skimming devices. Phenolic water generated in coke ovens & by-product plant attached to an integrated steel plant containing phenol in concentration of less than 100 mg/litre can be removed byAnswer: Treating in biological oxygen pond