Separation Techniques Lesson 1 Quiz

What is a mixture?

• A single substance with a uniform composition
• Two or more substances that are chemically combined
• Two or more substances that are physically combined
• A substance that cannot be separated

Which of the following is NOT a physical change?

• Dissolving sugar in water
• Melting ice
• Burning wood
• Freezing water

What property is primarily used in the technique of sieving?

• Density
• Solubility
• Particle size
• Boiling point

In sedimentation, what happens to denser particles?

• They float to the top
• They dissolve in the liquid
• They settle at the bottom
• They remain suspended

Which separation technique involves pouring off a liquid from above settled particles?

• Centrifugation
• Decantation
• Filtration
• Evaporation

What is the main difference between homogeneous and heterogeneous mixtures?

• Homogeneous mixtures have a uniform composition; heterogeneous do not
• Heterogeneous mixtures can be separated; homogeneous cannot
• Homogeneous mixtures are always liquids; heterogeneous can be solids
• There is no difference

Which of the following best describes centrifugation?

• Separating based on boiling point
• Separating based on particle size
• Rapidly spinning a mixture to separate components
• Allowing particles to settle naturally

What is miscibility?

• The ability of a solid to dissolve in a liquid
• The ability of two liquids to mix completely
• The ability of a gas to dissolve in a liquid
• The ability of a liquid to evaporate

Which of the following substances is immiscible with water?

• Ethanol
• Salt
• Oil
• Sugar

What is the primary factor that determines the effectiveness of sedimentation?

• Temperature
• Density
• Color
• Volume