A) Carbon dioxide B) Acetone C) Methanol D) Water
A) Gas B) Liquid C) Solid D) Supercritical
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) Increase column temperature C) Avoid solvent contamination D) Maintain supercritical conditions
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) Critical point B) Near-critical region C) Supercritical zone D) Transition zone
A) Gas B) Aqueous C) Liquid D) Solid
A) Through exposure to light. B) By altering its chemical composition. C) By changing the pressure and temperature, allowing fine-tuning between liquid-like and gas-like states. D) By adding impurities.
A) When one component is much more volatile than the other, at high pressure and temperatures above the component critical points. B) In all binary mixtures without exception. C) Only when both components have identical critical points. D) At low pressures regardless of temperature.
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) Equations of state, such as the Peng–Robinson or group-contribution methods. B) By averaging the boiling points of the components. C) Using only empirical observations without calculations. D) Through direct measurement at all possible pressures and temperatures.
A) The critical point B) The melting curve C) The density-pressure line D) The boiling curve
A) 570 MPa B) 7.38 MPa (73.8 bar) C) 3.4 MPa (34 bar) D) 40 bar
A) The density fluctuates unpredictably B) The density remains constant C) The density decreases significantly D) The density becomes higher
A) 3.4 MPa (34 bar) B) 570 MPa C) 7.38 MPa (73.8 bar) D) 14,000 MPa
A) Benjamin Thompson B) Baron Charles Cagniard de la Tour C) Michael Faraday D) James Prescott Joule
A) Pharmaceuticals B) Food science C) Microelectronics D) Cosmetics
A) 735 K B) 300 K C) 273 K D) 500 K
A) 12.0 megapascals B) 5.0 megapascals C) 9.3 megapascals D) 1.0 megapascal
A) Supercritical fluid extraction equipment. B) CO2-based dry cleaning equipment. C) Biomass gasification reactors. D) Hydrogen production facilities.
A) Rapid diffusion accelerates diffusion-controlled reactions. B) They are cheaper than conventional solvents. C) They increase reaction time. D) They eliminate the need for catalysts.
A) 100–10000 nm B) 10–5000 µm C) 50–500 nm D) 5–2000 nm
A) It speeds up the drying process significantly. B) It reduces the cost of materials used. C) It enhances the mechanical strength of the aerogel. D) It removes solvent without causing distortion due to surface tension.
A) It uses less energy to heat the water. B) It decreases the need for catalysts. C) It eliminates bubbles on electrodes, reducing ohmic losses. D) It increases the volume of hydrogen produced.
A) Lignin is completely converted into simple sugars. B) Aliphatic inter-ring linkages are cleaved into low molecular weight mixed phenols. C) Lignin forms a protective layer around polysaccharides. D) Lignin remains unchanged due to short reaction times.
A) The process requires long reaction times to be effective. 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) Large amounts of water are needed to maintain the reaction.
A) H2, CH4, CO2, CO B) NH3, SO2, NOx C) O2, N2, Ar D) Neon, Krypton, Xenon
A) Fermentation B) Oxidation C) Hydrogenation D) Transesterification
A) Rankine cycle B) Brayton cycle C) Otto cycle D) The Allam cycle
A) Similar thermal efficiency gains. B) Reduced radiation exposure. C) Lower operational costs. D) Increased fuel availability.
A) North Sea gas field B) Sleipner gas field C) Texas gas field D) Alaska gas field
A) China B) South Korea C) Japan D) India
A) Increased viscosity B) Enhanced conductivity C) Reduced density D) Antimicrobial properties |