CLASSIFICATION OF MATTER

CHEMICAL COMPOSITION OF MATTER

PURE SUBSTANCE

A sample of matter, either an element or a compound, that consists of only one component with definite physical and chemical properties and a definite composition.

CHEMICAL COMPOSITION OF MATTER

Classification of Pure Substances

CHEMICAL COMPOSITION OF MATTER

Classification of Mixtures

HETEROGENEOUS MIXTURES

HETEROGENEOUS: A mixture in which the uneven texture is visible to the naked eye or with a microscope

• Properties in one region differ from another

HOMOGENEOUS MIXTURE (SOLUTION)

HOMOGENEOUS:

• Completely uniform

• Two or more substances in the same phase

• Same properties throughout the sample

Example: Salt(NaCl) water(H2O)

(solution of sodium chloride dissolved in water)

•Mixtures can be separated by physical means into two or more pure substances

• Each pure substance can be classified as either an ELEMENT or a COMPOUND.

KINDS OF MIXTURES

1. SOLUTION

A mixture in which one or more substances are uniformly distributed in another substance.

• SOLUTE - The substance being dissolved in a solution.

• SOLVENT - The substance in which the solute was dissolved.

Example: sugar and water

CONCENTRATION - A measurement of the amount of solute dissolved in a fixed amount of solution.

Solutions can become saturated

SATURATION - Is the point where no more solute will dissolve.

A solution can cause ionic compounds to dissociate

DISSOCIATION - Is the separation of ion pairs.

AQUEOUS SOLUTIONS - A solution in which water is the solvent.

- Are universally important to living organisms.

An ion  is an atom or molecule in which

the total number of electrons is not equal to the total number of protons, giving the atom a

net positive or negative electrical charge.

2. SUSPENSION

- A mixture in which particles spread through a liquid or a gas but settle out over time

- The particles in a suspension are large than solute particles in a solution

Blood is an example of a suspension

3. COLLOIDS

- Also called colloidal suspensions

- Mixtures in which particles do not settle out over time

- Particles in a colloid are intermediate in size between particles in a solution and those in a suspension

Example: MILK

Colloids Have Two States Of Existence

• SOL STATE - The liquid state of a colloid

• GEL STATE - A jell-o like state of a colloid that forms when the sol state is cooled

A colloid can change from a sol to a gel and from a gel to a sol

CLASSIFICATION OF MATTER: SUMMARY