A) Acetone B) Water C) Carbon dioxide D) Methanol
A) Liquid B) Gas C) Supercritical D) Solid
A) Differences in molecular weight B) Differences in boiling point C) Differences in solubility in the mobile phase D) Differences in conductivity
A) Enhance detector sensitivity B) Maintain supercritical conditions C) Avoid solvent contamination D) Increase column temperature
A) Lower equipment cost B) Limited application range C) Faster separation D) Higher resolution
A) Improves stationary phase selectivity B) Enhances analyte solubility C) Reduces detector interference D) Stabilizes column efficiency
A) Transition zone B) Near-critical region C) Critical point D) Supercritical zone
A) Solid B) Gas C) Aqueous D) Liquid
A) Through exposure to light. B) By changing the pressure and temperature, allowing fine-tuning between liquid-like and gas-like states. C) By adding impurities. D) By altering its chemical composition.
A) At low pressures regardless of temperature. B) Only when both components have identical critical points. C) In all binary mixtures without exception. D) When one component is much more volatile than the other, at high pressure and temperatures above the component critical points.
A) As the arithmetic mean of the critical temperatures and pressures of the two components. B) Using only the critical temperature of one component. C) It cannot be estimated; it must always be measured experimentally. D) By summing the critical points of each component.
A) Through direct measurement at all possible pressures and temperatures. B) By averaging the boiling points of the components. C) Using only empirical observations without calculations. D) Equations of state, such as the Peng–Robinson or group-contribution methods.
A) The boiling curve B) The critical point C) The density-pressure line D) The melting curve
A) 40 bar B) 3.4 MPa (34 bar) C) 7.38 MPa (73.8 bar) D) 570 MPa
A) The density fluctuates unpredictably B) The density remains constant C) The density becomes higher D) The density decreases significantly
A) 7.38 MPa (73.8 bar) B) 570 MPa C) 14,000 MPa D) 3.4 MPa (34 bar)
A) Baron Charles Cagniard de la Tour B) Benjamin Thompson C) Michael Faraday D) James Prescott Joule
A) Pharmaceuticals B) Microelectronics C) Food science D) Cosmetics
A) 500 K B) 735 K C) 273 K D) 300 K
A) 5.0 megapascals B) 1.0 megapascal C) 12.0 megapascals D) 9.3 megapascals
A) Biomass gasification reactors. B) Supercritical fluid extraction equipment. C) Hydrogen production facilities. D) CO2-based dry cleaning equipment.
A) They increase reaction time. B) They are cheaper than conventional solvents. C) They eliminate the need for catalysts. D) Rapid diffusion accelerates diffusion-controlled reactions.
A) 50–500 nm B) 100–10000 nm C) 10–5000 µm D) 5–2000 nm
A) It enhances the mechanical strength of the aerogel. B) It removes solvent without causing distortion due to surface tension. C) It speeds up the drying process significantly. D) It reduces the cost of materials used.
A) It eliminates bubbles on electrodes, reducing ohmic losses. B) It increases the volume of hydrogen produced. C) It uses less energy to heat the water. D) It decreases the need for catalysts.
A) Lignin remains unchanged due to short reaction times. B) Lignin is completely converted into simple sugars. C) Aliphatic inter-ring linkages are cleaved into low molecular weight mixed phenols. D) Lignin forms a protective layer around polysaccharides.
A) Large amounts of water are needed to maintain the reaction. B) Supercritical conditions can only be achieved at low pressures. C) A continuous reaction system must be devised due to very short reaction times. D) The process requires long reaction times to be effective.
A) O2, N2, Ar B) H2, CH4, CO2, CO C) NH3, SO2, NOx D) Neon, Krypton, Xenon
A) Hydrogenation B) Transesterification C) Oxidation D) Fermentation
A) Otto cycle B) Brayton cycle C) The Allam cycle D) Rankine cycle
A) Lower operational costs. B) Reduced radiation exposure. C) Increased fuel availability. D) Similar thermal efficiency gains.
A) Texas gas field B) Sleipner gas field C) North Sea gas field D) Alaska gas field
A) Japan B) India C) South Korea D) China
A) Reduced density B) Enhanced conductivity C) Increased viscosity D) Antimicrobial properties |