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