Mixtures and Pure Substances

What is a mixture?

• A mixture is a solution that cannot be separated into its components.

• A mixture is a combination of two or more substances that are not chemically bonded.

• A mixture is a single substance with a uniform composition.

• A mixture is a chemical reaction between two substances.

Define a pure substance.

• A pure substance is a mixture of different compounds.

• A pure substance is always a liquid at room temperature.

• A pure substance can contain multiple types of particles.

• A pure substance is a material with a uniform and definite composition, consisting of only one type of particle.

Give an example of a homogeneous mixture.

• Saltwater

• Oil

• Air

• Sand

What is a heterogeneous mixture?

• A heterogeneous mixture is a mixture where the components are not evenly distributed and can be visually distinguished.

• A homogeneous mixture with uniform composition.

• A mixture that cannot be separated into its components.

• A solution where solutes are completely dissolved in a solvent.

How can you separate a mixture?

• Add more substances to the mixture

• Use methods like filtration, distillation, evaporation, or chromatography.

• Mix the components thoroughly

• Increase the temperature of the mixture

What is filtration used for?

• Filtration is used for heating substances.

• Filtration is used for mixing liquids together.

• Filtration is used for separating solids from liquids or gases.

• Filtration is used for creating solid materials.

Explain the process of evaporation in separating mixtures.

• Evaporation mixes the solute and solvent into a single phase.

• Evaporation requires the addition of a chemical to separate the components.

• Evaporation separates mixtures by heating to vaporize the solvent, leaving the solute behind.

• Evaporation cools the mixture, causing the solute to crystallize.

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What is the difference between a solution and a suspension?

• A solution can be separated by filtration, while a suspension cannot.

• A solution is homogeneous and fully dissolved, while a suspension is heterogeneous with undissolved particles.

• A suspension is always clear and transparent.

• A solution contains larger particles than a suspension.

Name a method to separate solids from liquids.

• Evaporation

• Distillation

• Centrifugation

• Filtration

Why is it important to understand mixtures and pure substances?

• To learn about the history of chemistry.

• It is important to understand mixtures and pure substances to distinguish between different types of matter and their properties.

• To memorize the names of all elements.

• To understand the importance of cooking techniques.

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