Materials Classification

What is solubility?

• Solubility is the ability of a substance to evaporate in a solvent

• Solubility is the process of solidifying a substance

• Solubility is the measurement of a substance's weight

• Solubility is the ability of a substance to dissolve in a solvent.

Give an example of a substance that is soluble in water.

• Salt (NaCl)

• Oil

• Sugar

• Iron

Explain how density is related to flotation.

• Flotation depends on the shape of the object

• Density has no impact on flotation

• Flotation is determined by the color of the object

• Density determines whether an object will sink or float in a fluid.

How can you test the solubility of an unknown substance?

• Ask a friend to taste the unknown substance

• Add the unknown substance to a known solvent and observe if it dissolves.

• Heat the unknown substance with a blowtorch

• Mix the unknown substance with gasoline and light it on fire

Why is flotation used in the mining industry?

• To walk dogs

• To separate valuable minerals from ore

• To fly airplanes

• To bake cookies

Name a common substance that is insoluble in water.

• Salt

• Sand

• Sugar

• Oil

What is the principle behind flotation in separating minerals?

• Minerals dissolve in water

• Minerals sink due to their weight

• Surface properties such as hydrophobicity of minerals allow them to attach to air bubbles in a water-based slurry, leading to separation.

• Minerals are attracted to each other

How does the density of an object affect its ability to float?

• Objects with higher density will float

• Objects with lower density than the fluid they are placed in will float, while objects with higher density will sink.

• Objects with lower density will sink

• Density has no impact on floating ability

What are some applications of flotation in the recycling industry?

• Using flotation to sort glass from paper

• Applying flotation to separate organic waste from plastics

• Some applications of flotation in the recycling industry include separating plastics from metals, removing paper from plastics, and recovering valuable materials like aluminum from mixed waste streams.

• Utilizing flotation to extract gold from electronic waste

Describe a method to determine the solubility of a substance.

• Heat the substance and see if it changes its physical state.

• Conduct an experiment by adding the substance to a solvent and observing if it dissolves completely or forms a precipitate.

• Ask a friend for their opinion on the substance's solubility.

• Mix the substance with water and observe the color change.