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