Environmental Engineering in CE Lagoons used for purification of polluted water All of these Use micro-organisms/bacteria in presence of dissolved oxygen Gives an excellent final effluent (with 3 to 4 lagoons arranged in series) having suspended solid < 1 mg/litre and BOD = 3.8 mg/litre Are large shallow artificial lakes also known as clarification lakes, maturation ponds or oxidation ponds All of these Use micro-organisms/bacteria in presence of dissolved oxygen Gives an excellent final effluent (with 3 to 4 lagoons arranged in series) having suspended solid < 1 mg/litre and BOD = 3.8 mg/litre Are large shallow artificial lakes also known as clarification lakes, maturation ponds or oxidation ponds ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE The term Biological Oxygen Demand (BOD) is used in relation to Industrial effluents Cooling water Potable water Distilled water Industrial effluents Cooling water Potable water Distilled water ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE The amount of chemical coagulant added for treatment of polluted water __________ with increase in temperature of the polluted water to be treated. Remains constant Increases Decreases May increase or decrease ; depends on the chemical characteristics of polluted water Remains constant Increases Decreases May increase or decrease ; depends on the chemical characteristics of polluted water ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE As per the world health organisation (WHO) specification, the maximum permissible concentration (i.e., TLV) of particulate matter in air is __________ μg/m³.(μg-microgram) 800 10 90 750 800 10 90 750 ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE Hydrogen ion concentration in distilled water is 7 x 10⁷ 10⁻⁷ 10⁷ 7 x 10⁻⁷ 7 x 10⁷ 10⁻⁷ 10⁷ 7 x 10⁻⁷ ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE Threshold limit value (TLV) means maximum permissible/acceptable concentration. TLV of phosgene in air is about __________ ppm (parts per million). 1.2 0.2 4.8 0.002 1.2 0.2 4.8 0.002 ANSWER DOWNLOAD EXAMIANS APP