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