Transcript Mixtures and Solutions

Mixtures and Solutions
Mixtures and Solutions
• A mixture is a combination
of two or more components that
are NOT chemically combined,
and retain their identities.
Mixtures can be physically separated.
The identities of the substances DO NOT
change.
A homogeneous mixture is also called a
solution.
Mixtures
• When a mixture’s components are easily
recognizable, such as pizza, it is called a
heterogeneous mixture.
• In a homogeneous mixture such
as chocolate milk, the component
particles cannot be distinguished,
even though they still retain their
original properties.
Mixtures
• Common Techniques for Separating Mixtures
Distillation – separates a mixture based on boiling
points of the component.
Examples :
saltwater
crude oil into gasoline and kerosene
Magnet – separates iron from other objects.
Centrifuge – spins and separates according to densities.
Solutions
• A mixture that appears to be a single
substance but is composed of particles
of two or more substances that are
distributed evenly amongst each other.
A solution may be liquid, gaseous, or solid.
Examples of solutions
Liquid - seawater
Gas - air
Solid - alloys
Solutions
• Dissolving – The process in which
particles of substances separate and
spread evenly amongst each other.
• Solute – substance that is dissolved. A solute is
soluble, or able to dissolve.
• A substance that is insoluble is unable to
dissolve, forms a mixture that is not
homogeneous, and therefore NOT a solution.
• Solvent – substance in which solute is dissolved.
Solubility
• The solubility of a solute is the amount of solute needed
to make a saturated solution using a given amount of
solvent at a certain temperature.
• Solubility is usually expressed in grams of solute per 100
ml of solvent (g/100ml)
• Three (3) methods that affect solubility
– Mixing, stirring, or shaking
– Heating
– Crushing or grinding
Suspension
• A mixture in which particles of
a material are dispersed throughout a liquid or gas but are large
enough that they settle out.
– Particles are insoluble, so they DO NOT
dissolve in the liquid or gas.
– Particles can be separated using a filter.
• Examples:
• Salad dressing
• Medicines that say
“shake well before use”
Colloids
• A mixture in which the particles are
dispersed throughout but are not heavy
enough to settle out.
• Made up of solids, liquids and gases.
– Examples :
• Mayonnaise
• Stick deodorant
• milk