Matter: Properties and Changes Mixtures What is a mixture? when two or more substances are combined the individual substances retain their individual chemical.

Matter: Properties and ChangesMixtures

What is a mixture? when two or more substances are combined

the individual substances retain their individual chemical properties

most everyday matter exists as mixtures

substances tend to mix naturally


a common mixture is the mercury silver mixture in the filling

Although the two substances (mercury and silver) are not distinguishable in this picture, one could separate the mercury from the silver by heating the mixture.

The mercury will boil to a gas before the silver. You would be left with mercury gas and liquid silver, two separate substances.


Types of Mixtures -

heterogeneous mixtures - when the individual substances remain distinct, not blending smoothly throughout

example - salad dressings composed of oil, seasonings and vinegar, they will mix but remain distinguishable and if left for long periods of time, will separate out based on density.


Types of Mixtures -

homogeneous mixture - mixture that has a constant composition throughout, no one part has more of one substance than another part

these are often referred to as SOLUTIONS

example - most common examples of solutions in daily life are the liquids we are in contact with, like coffee, tea, soda, milk, even tap water

if you take a drink of a soda, the first sip will taste the same as the last, the concentrations of all the chemicals was uniform throughout


SOLUTIONS - solutions are not limited to liquids, they can be solids, liquids, gases, or combinations of liquid/gas, solid/liquid, solid/gas

gas/gas - air in a scuba tank composed of nitrogen, oxygen, and argongas/liquid - seawater has oxygen and carbon dioxide dissolved liquid/gas - moist air exhaled by a scuba diver contains water dropletsliquid/liquid - when it rains, fresh water mixes with seawatersolid/liquid - solid salt is dissolved in seawatersolid/solid - the air tank is made of a metal alloy, a mixture of two metals


Separating Mixtures - most matter exists naturally as a mixture

in order to understand matter, there was a need to separate the substances from each other using various techniquesFILTRATION - solutions of solid/liquid can be separated using this method

the solution is poured through a filter, trapping the solid while letting the liquid pass through


FILTRATION


DISTILLATION - this process can be used to separate most solutions

the solution is heated the part of the solution with the lowest

boiling point will phase change firstthe vapor can be directed, collected, and

allowed to condense


DISTILLATION

Matter: Properties and ChangesMixturesCRYSTALLIZATION - results in the formation of pure solid particles from a solution containing the dissolved substancewhen the solution contains as much dissolved substance as it can hold, the addition of even a little more substance can often cause the substance to come out of solution on any available surface

Matter: Properties and Changes

SUBLIMATION - process by which a solid phase changes into a gas, skipping the liquid phase

can be used to separate 2 solids when one sublimates, while the other does not

Matter: Properties and Changes

CHROMATOGRAPHY - technique that separates the components of a mixture based on the ability of each component to travel or be drawn across the surface of another material

Matter: Properties and Changes Mixtures What is a mixture? when two or more substances are combined the individual substances retain their individual chemical.

Documents

mixtures substances

substances mercury

separate substances

mercury silver mixture

individual chemical

homogeneous mixture

common mixture

everyday matter