Solution Chemistry

REMEMBER THIS?

MATTER

Can it be physically separated?

Homogeneous Mixture

(solution)

Heterogeneous Mixture Compound Element

MIXTURE PURE SUBSTANCE

yes no

Can it be chemically decomposed?

noyesIs the composition uniform?

noyes

Colloids Suspensions

KEY TERMS

• suspension—a solution that appears uniform while being stirred but separates quickly after stirring

• solution—a homogenous mixture• colloid—a mixture in which small particles are

suspended throughout• solvent - the substance in which the solute is

dissolved• solute - the substance dissolved

Mixtures• Mixtures consist of 2 or more substances

that can be physically separated.• Mixtures can either be heterogeneous or

homogeneous. • The particles of a heterogeneous mixture

are large enough to see under a microscope.• In a homogeneous mixture, however, the particles

are molecule-sized, so the mixture appears uniform, even under a microscope

• A solution is a homogeneous mixture of two or more substances uniformly dispersed throughout a single phase.

Heterogeneous Mixtures: Suspensions• A suspension is a temporary mixture in which

particles of a material are more or less evenly dispersed throughout a liquid or gas.

• In a suspension, the particles may remain mixed with the liquid while the liquid is being stirred, but later they settle to the bottom.

Suspension Particle Model

Heterogeneous Mixtures: Colloids Colloids are stable heterogeneous mixtures.

Particles are not evenly dispersed when looked at under a microscope.

Particles do not settle out and remain suspended in solution.

Examples: milk, fog

SOLUTION INFORMATION• Any mixture that is homogeneous on a

microscopic level is a solution. According to that definition, air is a gaseous solution.

• A homogeneous liquid mixture has one main component—a liquid—as well as one or more additional ingredients that are usually present in smaller amounts.

Aqueous solutions• The primary ingredient in a solution is called

the solvent.• The other ingredients are the solutes and are

said to be dissolved in the solvent.• Water is the most common solvent.• Water is a unique solvent because so many

substances can dissolve in it. • Solutions in which water is the solvent are

called aqueous solutions.

POGIL Assign a role to each member of your team

Leader: Ensures everyone is fulfilling their roles. Works with Time keeper, recorder and reflector to keep the team running smoothly and on task. This is the only person permitted to ask questions to the instructor or other groups.

Recorder: Records important discussions and key points. This person will record all answers into the POGIL packet, and ensure all group members names are included.

Presenter/Reflector: Person responsible for reporting orally to the class. This is the only person who should speak. Also reports and observes group dynamics. This person may be responsible for reporting on how the group worked together at any point.

Reader/Time Keeper: Reads the material and questions aloud. Signal speakers when they are close to the end of their allotted time. Provide 1 minute of quiet thinking time after each question read Each person is allotted two minutes to speak uninterrupted. When there are 15

seconds left, please say that softly. When the full time has been used, say "time."