Chemistry ยท Science General
Separation Techniques
842 Questions
Separation techniques involve physical methods to isolate mixtures, including distillation, filtration, and crystallization. Competitive exams frequently test these foundational concepts. Review the exact processes to enhance problem solving speed.
Distillation and evaporationCrystallization processFiltration methodsSeparating dissolved solidsChromatography and mass techniques
Separation Techniques Questions
What is the name of the technique used to create a clear liquid from a cloudy or opaque liquid?
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Spherification
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Emulsification
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Gelatinization
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Clarification
D
Correct answer
Explanation
Clarification is a technique used in molecular gastronomy to create a clear liquid from a cloudy or opaque liquid by removing impurities and solids.
What is the name of the technique used to create a gel from a liquid?
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Spherification
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Emulsification
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Gelatinization
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Clarification
C
Correct answer
Explanation
Gelatinization is a technique used in molecular gastronomy to create a gel from a liquid by adding a gelling agent, such as agar-agar or gelatin.
What is the name of the technique used to create a liquid from a solid?
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Spherification
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Emulsification
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Gelatinization
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Liquefaction
D
Correct answer
Explanation
Liquefaction is a technique used in molecular gastronomy to create a liquid from a solid by heating or dissolving the solid.
What is the term used to describe the process of separating milk into its liquid and solid components?
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Homogenization
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Pasteurization
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Coagulation
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Centrifugation
D
Correct answer
Explanation
Centrifugation is the process of separating milk into its liquid and solid components by spinning it at high speeds, causing the heavier solids to settle at the bottom.
What is the process of separating solids from liquids in food processing called?
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Filtration
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Centrifugation
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Evaporation
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Distillation
A
Correct answer
Explanation
Filtration is a process used in food processing to separate solids from liquids by passing the mixture through a filter medium that allows the liquid to pass through while retaining the solids.
What is the process of removing impurities from food using a semipermeable membrane called?
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Filtration
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Centrifugation
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Evaporation
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Dialysis
D
Correct answer
Explanation
Dialysis is a process used in food processing to remove impurities from food by passing it through a semipermeable membrane that allows smaller molecules to pass through while retaining larger molecules.
Which technique separates molecules based on their size and charge?
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Gel Electrophoresis
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Chromatography
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Spectrophotometry
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Microscopy
A
Correct answer
Explanation
Gel electrophoresis is a technique used to separate molecules based on their size and charge. It is commonly used to separate DNA, RNA, and proteins.
What is the principle behind the operation of an ion chromatograph?
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Separation of ions based on their size
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Separation of ions based on their charge
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Separation of ions based on their mass
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Separation of ions based on their volatility
B
Correct answer
Explanation
Ion chromatography is a technique used to separate and measure ions in a sample. It works by passing the sample through a column packed with a stationary phase that has a specific affinity for certain ions. The ions are separated based on their charge and elute from the column at different times.
What is the role of a stationary phase in gas chromatography?
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To dissolve the sample
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To carry the sample through the column
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To separate the analytes
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To detect the analytes
C
Correct answer
Explanation
In gas chromatography, the stationary phase is a solid or liquid coating on the inside of the chromatographic column. The stationary phase interacts with the analytes in the sample, causing them to separate and elute from the column at different times.
Which of the following is a common method for detecting and measuring volatile organic compounds (VOCs) in water samples?
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Gas chromatography-mass spectrometry (GC-MS)
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High-performance liquid chromatography (HPLC)
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Atomic absorption spectroscopy (AAS)
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Inductively coupled plasma mass spectrometry (ICP-MS)
A
Correct answer
Explanation
GC-MS is commonly used for the analysis of VOCs in water samples due to its high sensitivity and ability to separate and identify a wide range of compounds. VOCs are typically purged from the water sample and then analyzed by GC-MS.
What is the purpose of a chromatography column in a bioprocess?
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To separate different molecules in a mixture
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To purify a product
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To concentrate a product
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To remove impurities from a product
A
Correct answer
Explanation
Chromatography columns are used to separate different molecules in a mixture based on their different properties.
Which of the following is not a type of chromatography used in bioprocessing?
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Size exclusion chromatography
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Ion exchange chromatography
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Affinity chromatography
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Gas chromatography
D
Correct answer
Explanation
Gas chromatography is not typically used in bioprocessing, as it is not well-suited for the separation of large molecules.
Which of the following is a common method for ensuring the sterility of pharmaceutical products?
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Sterilization by heat
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Sterilization by filtration
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Sterilization by radiation
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Sterilization by chemical agents
Correct answer
Explanation
Pharmaceutical products can be sterilized using various methods, including sterilization by heat, filtration, radiation, and chemical agents, to eliminate microorganisms and ensure product sterility.
Which of the following is NOT a common type of downstream processing operation used in bioprocessing?
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Filtration
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Centrifugation
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Chromatography
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Crystallization
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Drying
E
Correct answer
Explanation
Drying is not a common type of downstream processing operation used in bioprocessing, as it is typically used for the production of solid products, which are not common in bioprocessing.
Which of the following is NOT a common type of bioseparation technique used in bioprocessing?
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Filtration
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Centrifugation
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Chromatography
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Extraction
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Precipitation
D
Correct answer
Explanation
Extraction is not a common type of bioseparation technique used in bioprocessing, as it is typically used for the separation of non-polar compounds from polar compounds.