【Test Your Knowledge】Basic Chemical Engineering Knowledge (24)
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1. The characteristics of a vortex pump are head ( ), pressure ( ), and flow rate ( ). 2. The molecular weight of the urea molecule with the formula CO(NH2)2 is ( ), the mass ratio of various elements is ( ), and the percentage content of nitrogen is ( ). 3. The process of product quality formation is ( ), ( ), ( ), ( ). 4. The vaporization phenomenon that occurs only on the surface of a liquid is called ( ). It can be divided into ( ) and ( ). 5. Alternating current refers to a current in which both ( ) and ( ) change periodically over time. 6. The safe voltage should be below 110 volts. （ ） 7. The shaft seal of a reciprocating vacuum pump is used to seal the gap between the cylinder and the piston rod. （ ） 8. The boiling point of a solution can be increased during vacuum distillation. （ ） 9. In the compound FeCl3, the oxidation state of iron is 2, while in FeCl2 it is 3. ( ) 10. The higher the sensitivity value of an instrument, the more sensitive it is. ( ) Reference answers: 1. Large, Large, Small 2. 60; H:C:O:N=1:3:4:7; 46.6% 3. Design, Production, Inspection, Use 4. Evaporation, Natural evaporation, Forced evaporation 5. Size, Direction 6. Wrong ； 7. Wrong ； 8. Wrong ； 9. Wrong ； 10. Yes ； Did you get it right? This post was last edited by zhangyong6404 on 2009-4-7 18:19.]
1. The characteristics of vortex pumps are high head, high pressure, and low flow rate. 2. The molecular weight of urea is (60), and the mass ratio of its various elements is (3:4:7:1); the percentage content of nitrogen is (67%). 3. The process of product quality formation includes (design and trial production process), (manufacturing process), (auxiliary production process), and (use process). Another alternative answer is (Plan, Do, Check, Action). 4. The vaporization phenomenon that occurs only on the surface of a liquid is called (evaporation). It can be divided into (at atmospheric pressure evaporation) and (under reduced pressure evaporation). 5. Alternating current refers to an electric current whose (magnitude) and (direction) both change periodically over time. 6. The safe voltage should be below 110 volts. (Incorrect) 7. The shaft seal of a reciprocating vacuum pump is used to seal the gap between the cylinder and the piston rod. (Incorrect) 8. The boiling point of a solution can be increased during vacuum distillation. (Incorrect) 9. In the compound FeCl3, the oxidation state of iron is 2, while in FeCl2 it is 3. (Incorrect) 10. The higher the sensitivity value of an instrument, the more sensitive it is. (Yes) This post was last edited by wbp on 2009-4-6 21:37.]
1. The characteristics of vortex pumps are high head (with a rapid drop), low pressure, and low flow rate. 2. The molecular weight of urea is (60), and the mass ratio of its various elements is (C:O:N:H = 12:16:28:4); the percentage content of nitrogen is (46.6%). 3. The process of product quality formation includes the procurement and supply process, the process control process, and the in-process quality control process, among others. 4. The vaporization phenomenon that occurs only on the surface of a liquid is called (evaporation). It can be divided into (evaporation) and (boiling). 5. Alternating current refers to a current whose (amplitude) and (direction) both change periodically over time. 6. The safe voltage should be below 110 volts. (Mistake) 7. The shaft seal of a reciprocating vacuum pump is used to seal the gap between the cylinder and the piston rod. (Mistake) 8. The boiling point of the solution can be increased during vacuum distillation. (Mistake) 9. In the compound FeCl3, the oxidation state of iron is 2, while in FeCl2 it is 3. (Mistake) 10. The higher the sensitivity value of an instrument, the more sensitive it is. (Mistake)
1. The characteristics of vortex pumps are high head (with a rapid drop), low pressure, and low flow rate. 2. The molecular weight of urea is (60), and the mass ratio of its various elements is (C:O:N:H = 12:16:28:4); the percentage content of nitrogen is (46.6%). 3. The process of product quality formation includes the procurement and supply process, the process control process, and the in-process quality control process, among others. 4. The vaporization phenomenon that occurs only on the surface of a liquid is called (evaporation). It can be divided into (evaporation) and (boiling). 5. Alternating current refers to a current whose (amplitude) and (direction) both change periodically over time. 6. The safe voltage should be below 110 volts. (Mistake) 7. The shaft seal of a reciprocating vacuum pump is used to seal the gap between the cylinder and the piston rod. (Mistake) 8. The boiling point of the solution can be increased during vacuum distillation. (Mistake) 9. In the compound FeCl3, the oxidation state of iron is 2, while in FeCl2 it is 3. (Mistake) 10. The higher the sensitivity value of an instrument, the more sensitive it is. (Mistake)
1. The characteristics of vortex pumps are high head, high pressure, and low flow rate. 2. The molecular weight of urea is (60), and the mass ratio of its various elements is (3:4:7:1); the percentage content of nitrogen is (67%). 3. The process of product quality formation is (planning), (execution), (inspection), and (action). 4. The vaporization phenomenon that occurs only on the surface of a liquid is called (evaporation). It can be divided into (at atmospheric pressure evaporation) and (under reduced pressure evaporation). 5. Alternating current refers to an electric current whose (magnitude) and (direction) both change periodically over time. 6. The safe voltage should be below 110 volts. (Incorrect) 7. The shaft seal of a reciprocating vacuum pump is used to seal the gap between the cylinder and the piston rod. (Incorrect) 8. The boiling point of a solution can be increased during vacuum distillation. (Incorrect) 9. In the compound FeCl3, the oxidation state of iron is 2, while in FeCl2 it is 3. (Incorrect) 10. The higher the sensitivity value of an instrument, the more sensitive it is. (Yes)
1. The characteristics of vortex pumps are high head, high pressure, and low flow rate. 2. The molecular weight of urea is (60), and the mass ratio of its various elements is (C:O:N:H = 3:4:7:1); the percentage content of nitrogen is (46.7%). 3. The process of product quality formation is (procurement), (production), (inspection), and (sales). 4. The vaporization phenomenon that occurs only on the surface of a liquid is called (evaporation). It can be divided into (evaporation) and (boiling). 5. Alternating current refers to an electric current whose (magnitude) and (direction) both change periodically over time. 6. The safe voltage should be below 110 volts. (Incorrect) 7. The shaft seal of a reciprocating vacuum pump is used to seal the gap between the cylinder and the piston rod. (Incorrect) 8. The boiling point of a solution can be increased during vacuum distillation. (Incorrect) 9. In the compound FeCl3, the oxidation state of iron is 2, while in FeCl2 it is 3. (Incorrect) 10. The higher the sensitivity value of an instrument, the more sensitive it is. ( Wrong )
1. The characteristics of vortex pumps are high head, high pressure, and low flow rate. 2. The molecular weight of urea is 60, and the mass ratio of its constituent elements is C:O:N:H = 12:16:28:4; the percentage content of nitrogen is 46.6%. 3. The process of product quality formation consists of the procurement supply process, the process control process, and the in-process quality control process. 4. The vaporization phenomenon that occurs only on the surface of a liquid is called evaporation. It can be divided into atmospheric evaporation and vacuum evaporation. 5. Alternating current refers to current whose magnitude and direction both change periodically over time. 6. The safe voltage should be below 110 volts. Wrong 7: The shaft seal of a reciprocating vacuum pump is used to seal the gap between the cylinder and the piston rod. Wrong 8: The boiling point of the solution can be increased during vacuum distillation. Wrong 9: In the compound FeCl3, the oxidation state of iron is 2, while in FeCl2 it is 3. Wrong 10: The higher the sensitivity value of an instrument, the more sensitive it is. Yes
1. The characteristics of vortex pumps are high head, high pressure, and low flow rate. 2. The molecular weight of urea is (60), and the mass ratio of its various elements is (3:4:7:1); the percentage content of nitrogen is (67%). 3. The process of product quality formation is (P planning), (D execution), (C inspection), and (A action). 4. The vaporization phenomenon that occurs only on the surface of a liquid is called (evaporation). It can be divided into (at atmospheric pressure evaporation) and (under reduced pressure evaporation). 5. Alternating current refers to an electric current whose (magnitude) and (direction) both change periodically over time. 6. The safe voltage should be below 110 volts. (Incorrect) 7. The shaft seal of a reciprocating vacuum pump is used to seal the gap between the cylinder and the piston rod. (Incorrect) 8. The boiling point of a solution can be increased during vacuum distillation. (Incorrect) 9. In the compound FeCl3, the oxidation state of iron is 2, while in FeCl2 it is 3. (Incorrect) 10. The higher the sensitivity value of an instrument, the more sensitive it is. (Yes)
1. The characteristics of vortex pumps are high head, high pressure, and low flow rate. 2. The molecular weight of urea is (60), and the mass ratio of its various elements is (3:4:7:1); the percentage content of nitrogen is (67%). 3. The process of product quality formation is (planning), (execution), (inspection), and (action). 4. The vaporization phenomenon that occurs only on the surface of a liquid is called (evaporation). It can be divided into (at atmospheric pressure evaporation) and (under reduced pressure evaporation). 5. Alternating current refers to an electric current whose (magnitude) and (direction) both change periodically over time. 6. The safe voltage should be below 110 volts. (Incorrect) 7. The shaft seal of a reciprocating vacuum pump is used to seal the gap between the cylinder and the piston rod. (Incorrect) 8. The boiling point of a solution can be increased during vacuum distillation. (Incorrect) 9. In the compound FeCl3, the oxidation state of iron is 2, while in FeCl2 it is 3. (Incorrect) 10. The higher the sensitivity value of an instrument, the more sensitive it is. ( Wrong )
plan.do.check,action
1. The characteristics of vortex pumps are high head (with a rapid drop), low pressure, and low flow rate. 2. The molecular weight of urea is (60), and the mass ratio of its constituent elements is (C:O:N:H = 3:4:7:1); the percentage content of nitrogen is (47%). 3. The process of product quality formation is (planning), (execution), (inspection), (action). 4. The vaporization phenomenon that occurs only on the surface of a liquid is called (evaporation). It can be divided into (evaporation) and (boiling). 5. Alternating current refers to an electric current whose (magnitude) and (direction) both change periodically over time. 6. The safe voltage should be below 110 volts. (F) 7. The shaft seal of a reciprocating vacuum pump is used to seal the gap between the cylinder and the piston rod. (F) 8. The boiling point of the solution can be increased during vacuum distillation. (F) 9. In the compound FeCl3, the oxidation state of iron is 2, while in FeCl2 it is 3. (F) 10. The higher the sensitivity value of the instrument, the more sensitive it is. (F)
1. High, small, large. 2, 60, C:O:N:H = 3:4:7:1, 47%. 3. Plan, execute, check, act. 4. Evaporation: atmospheric pressure evaporation, vacuum evaporation (boiling also occurs inside the liquid!). 5. Size, direction. 6. Wrong. 7. Wrong. 8. Wrong. 9. Wrong. 10. Wrong.
Types: Centrifugal pump, Reciprocating pump, Rotary pump, Vortex pump.
Flow rate: 1. Uniform. 2. Large volume. 3. Flow rate varies depending on the pipeline conditions. 1. Non-uniform. 2. Small volume. 3. Flow rate remains constant, with little change even with changes in head pressure. 1. Relatively uniform. 2. Small volume. 3. Flow rate is constant, same as that of a reciprocating pump. 1. Uniform. 2. Large volume. 3. Flow rate varies depending on the pipeline conditions.
Head pressure: 1. Generally not high. 2. Only a certain head pressure can be provided for a given flow rate. 1. Relatively high. 2. Different head pressures can be supplied for a given flow rate, determined by the piping system. 1. Relatively high. 2. Different head pressures can be supplied for a given flow rate, determined by the piping system. 1. Relatively high. 2. Only a certain head pressure can be provided for a given flow rate.
Efficiency: 1. Around 70%. 2. Highest at the design point; efficiency decreases as deviation from this point increases. 1. Around 80%. 2. Efficiency remains high even when different head pressures are supplied. 1. Between 60% and 90%. 2. Leakage occurs at high head pressures, reducing efficiency. It is between 25% and 50%.
Structure: 1. Simple, inexpensive, and easy to install. 2. Rotates at high speed; can be directly connected to an electric motor. 3. Small size for the same flow rate. 4. High requirements for shaft sealing to prevent leaks. 1. Many parts, complex structure. 2. Severe vibration; cannot operate at high speeds; difficult to install. 3. Large size, occupies more space. 4. Requires suction and discharge valves. 5. Even more complex structure when transporting corrosive liquids. 1. No valves. 2. Can be directly connected to an electric motor. 3. Fewer parts, but high precision in manufacturing is required. 1. Simple and compact structure, with a high suction height. 2. Rotates at high speed; can be directly connected to an electric motor. 3. Very small clearance required between the impeller and the pump casing. 4. High requirements for shaft sealing to prevent leaks.
Operation: 1. Flush water before starting; no leaks during operation. 2. Easy to maintain and operate. 3. Flow rate can be easily adjusted using valves. 4. No damage occurs due to pipeline blockages. 1. Many parts, prone to failure; difficult to repair. 2. Flow rate can only be adjusted using bypass valves, as outlet valves are not available. 3. High efficiency can be maintained even when head pressure and flow rate change. 1. Inspection is more complicated than that of centrifugal pumps but easier than that of reciprocating pumps. 2. Flow rate can only be adjusted using bypass valves, as outlet valves are not available. 1. Power increases as flow rate decreases; the outlet valve should be opened when starting. 2. Similarly, bypass valves are used for flow rate adjustment
Types: Centrifugal pump, Reciprocating pump, Rotary pump, Vortex pump.
Flow rate: 1. Uniform. 2. Large volume. 3. Flow rate varies depending on the pipeline conditions. 1. Non-uniform. 2. Small volume. 3. Flow rate remains constant, with little change even with changes in head pressure. 1. Relatively uniform. 2. Small volume. 3. Flow rate is constant, same as that of a reciprocating pump. 1. Uniform. 2. Large volume. 3. Flow rate varies depending on the pipeline conditions.
Head pressure: 1. Generally not high. 2. Only a certain head pressure can be provided for a given flow rate. 1. Relatively high. 2. Different head pressures can be supplied for a given flow rate, determined by the piping system. 1. Relatively high. 2. Different head pressures can be supplied for a given flow rate, determined by the piping system. 1. Relatively high. 2. Only a certain head pressure can be provided for a given flow rate.
Efficiency: 1. Around 70%. 2. Highest at the design point; efficiency decreases as deviation from this point increases. 1. Around 80%. 2. Efficiency remains high even when different head pressures are supplied. 1. Between 60% and 90%. 2. Leakage occurs at high head pressures, reducing efficiency. It is between 25% and 50%.
Structure: 1. Simple, inexpensive, and easy to install. 2. Rotates at high speed; can be directly connected to an electric motor. 3. Small size for the same flow rate. 4. High requirements for shaft sealing to prevent leaks. 1. Many parts, complex structure. 2. Severe vibration; cannot operate at high speeds; difficult to install. 3. Large size, occupies more space. 4. Requires suction and discharge valves. 5. Even more complex structure when transporting corrosive liquids. 1. No valves. 2. Can be directly connected to an electric motor. 3. Fewer parts, but high precision in manufacturing is required. 1. Simple and compact structure, with a high suction height. 2. Rotates at high speed; can be directly connected to an electric motor. 3. Very small clearance required between the impeller and the pump casing. 4. High requirements for shaft sealing to prevent leaks.
Operation: 1. Flush water before starting; no leaks during operation. 2. Easy to maintain and operate. 3. Flow rate can be easily adjusted using valves. 4. No damage occurs due to pipeline blockages. 1. Many parts, prone to failure; difficult to repair. 2. Flow rate can only be adjusted using bypass valves, as outlet valves are not available. 3. High efficiency can be maintained even when head pressure and flow rate change. 1. Inspection is more complicated than that of centrifugal pumps but easier than that of reciprocating pumps. 2. Flow rate can only be adjusted using bypass valves, as outlet valves are not available. 1. Power increases as flow rate decreases; the outlet valve should be opened when starting. 2. Similarly, bypass valves are used for flow rate adjustment
1. The characteristics of vortex pumps are high head, high pressure, and low flow rate. 2. The molecular weight of urea is (60), and the mass ratio of its various elements is (C:O:N:H = 3:4:7:1); the percentage content of nitrogen is (46.7%). 3. The process of product quality formation is (procurement), (production), (inspection), and (sales). 4. The vaporization phenomenon that occurs only on the surface of a liquid is called (evaporation). It can be divided into (evaporation) and (boiling). 5. Alternating current refers to an electric current whose (magnitude) and (direction) both change periodically over time. 6. The safe voltage should be below 110 volts. (Incorrect) 7. The shaft seal of a reciprocating vacuum pump is used to seal the gap between the cylinder and the piston rod. (Incorrect) 8. The boiling point of a solution can be increased during vacuum distillation. (Incorrect) 9. In the compound FeCl3, the oxidation state of iron is 2, while in FeCl2 it is 3. (Incorrect) 10. The higher the sensitivity value of an instrument, the more sensitive it is. ( Wrong )
1. The characteristics of vortex pumps are high head, low pressure, and low flow rate. 2. The molecular weight of urea is (60), and the mass ratio of its various elements is (C:O:N:H = 3:4:7:1). The percentage content of nitrogen is (46.7%). 3. The process of product quality formation is (planning), (execution), (inspection), (action). 4. The vaporization phenomenon that occurs only on the surface of a liquid is called (evaporation). It can be divided into (at atmospheric pressure evaporation) and (under reduced pressure evaporation). 5. Alternating current refers to an electric current whose (magnitude) and (direction) both change periodically over time. 6. The safe voltage should be below 110 volts. (F) 7. The shaft seal of a reciprocating vacuum pump is used to seal the gap between the cylinder and the piston rod. (F) 8. The boiling point of the solution can be increased during vacuum distillation. (F) 9. In the compound FeCl3, the oxidation state of iron is 2, while in FeCl2 it is 3. (F) 10. The higher the sensitivity value of an instrument, the more sensitive it is. (F)
1. The characteristics of vortex pumps are high head, large pressure variation, and low flow rate. 2. The molecular weight of urea is (60), the mass ratio of its constituent elements is (), and the percentage content of nitrogen is (46%). 3. The process of product quality formation includes (market research and analysis, new product design and development, process planning and development), (procurement, manufacturing, inspection), (packaging and storage), (product sales and after-sales service). 4. The vaporization phenomenon that occurs only on the surface of a liquid is called (evaporation). It can be divided into ( ) and ( ). 5. Alternating current refers to an electric current whose (magnitude) and (direction) both change periodically over time. 6. The safe voltage should be below 110 volts. (F) 7. The shaft seal of a reciprocating vacuum pump is used to seal the gap between the cylinder and the piston rod. (F) 8. The boiling point of the solution can be increased during vacuum distillation. (F) 9. In the compound FeCl3, the oxidation state of iron is 2, while in FeCl2 it is 3. (F) 10. The higher the sensitivity value of an instrument, the more sensitive it is. (F)
1. High； large ； Small 2, 60 ； C：O：N：H=3：4：7：1 ； 46.7% 3. Design ； Process ； inspection ； Analysis and improvement (not very clear) 4. Evaporation ； boiling evaporation ； Natural evaporation 5. Size ； Direction 6, × 7, × 8, × 9, × 10,√
1. The characteristics of vortex pumps are high head, high pressure, and low flow rate. 2. The molecular weight of urea is (60), and the mass ratio of its various elements is (3:4:7:1); the percentage content of nitrogen is (67%). 3. The process of product quality formation is Plan, Do, Check, Action. 4. The vaporization phenomenon that occurs only on the surface of a liquid is called (evaporation). It can be divided into (at atmospheric pressure evaporation) and (under reduced pressure evaporation). 5. Alternating current refers to an electric current whose (magnitude) and (direction) both change periodically over time. 6. The safe voltage should be below 110 volts. (Incorrect) 7. The shaft seal of a reciprocating vacuum pump is used to seal the gap between the cylinder and the piston rod. (Incorrect) 8. The boiling point of a solution can be increased during vacuum distillation. (Incorrect) 9. In the compound FeCl3, the oxidation state of iron is 2, while in FeCl2 it is 3. (Incorrect) 10. The higher the sensitivity value of an instrument, the more sensitive it is. (Yes)
1 Size 2 60 C:O:N:H=3:4:7:1 46.7% 3 Design Process Inspection Treatment 4 Evaporation Evaporation at atmospheric pressure Evaporation under reduced pressure 5 Size Direction 6 Wrong 7 Wrong 8 Wrong 9 Wrong 10 Right
1 Size 2 60 C:O:N:H=3:4:7:1 46.7% 3 Design Process Inspection Treatment 4 Evaporation Evaporation at atmospheric pressure Evaporation under reduced pressure 5 Size Direction 6 Wrong 7 Wrong 8 Wrong 9 Wrong 10 Right
Diving into posts and writing replies for a long time. The original poster, please post a standard answer
1. The characteristics of vortex pumps are high head, high pressure, and low flow rate. 2. The molecular weight of urea, with the molecular formula CO(NH2)2, is 60; the mass ratio of its constituent elements is (C:O:N:H = 3:4:7:1), and the percentage content of nitrogen is 47%. 3. The process of product quality development is (Plan, Do, Check, Action). 4. The vaporization phenomenon that occurs only on the surface of a liquid is called (evaporation). It can be divided into (natural evaporation) and (boiling evaporation). 5. Alternating current refers to a type of current in which both (voltage) and (current) change periodically over time. 6. The safe voltage should be below 110 volts. (Incorrect) 7. The shaft seal of a reciprocating vacuum pump is used to seal the gap between the cylinder and the piston rod. (Incorrect) 8. The boiling point of a solution can be increased during vacuum distillation. (Incorrect) 9. In the compound FeCl3, the oxidation state of iron is 2, while in FeCl2 it is 3. (Incorrect) 10. The higher the sensitivity value of an instrument, the more sensitive it is. (Yes) This post was last edited by miller625 on 2009-4-7 09:51]