states of matter and mixtures Flashcards
what are some structures of solids
-fixed positions
-regular lattice arrangement
-definite shape
what are some properties of liquids
-free to move but still touch each other
dont have definite shape
what are some properties of gases
dont keep a definite shape
-has the most energy
what is solid to liquid
melting
what is liquid to solid
freezing
what is liquid to gas
evaporating
what is gas to liquid
condensing
what is solid to gas
subliming
what does it mean if a substance pure
it is made up of only a single element or compound
how do you test how pure a substance is
a pure substance has a fixed and specific melting and boiling point. by heating the substance and recording the melting point, you can compare it to the expected value. if it is a mixture, it will give a range of melting points
what are the two types of distillation
simple and fractional
what is simple distillation used for
separation of a liquid from a solution
how is the method of simple distillation carried out?
heat the mixture until the liquid is evaporated. then collect that liquid
what is fractional distillation used for?
separation of a mixture of liquids.
how is the method of fractional distillation carried out
place the mixture in a fractional column. as you heat this, the different liquids will have different boiling points so they will evaporate at different temperatures
what is filtration used for
to separate an insoluble solid from a liquid
what is crystalisation used for
separates a soluble solid from a solution
what is the mobile phase in chromotography
this is where the molecules can move. this is a liquid or gas
what is the stationary phase in chromotography
this is where the molecules cant move. this is a solid or a thick liquid
how do you calculate the rf value in chromotography
distance travelled by solute/distance travelled by solvent
what is potable water
water that is safe to drink
what are the three methods to purify water
-filtration
-sedimentation
-chlorination
what is the filtration method in the purification of water
a wire mesh screens out large solids
what is the sedimentation method in the purification of water
iron or aluminium sulfate is added to the water. this makes small particles stick together and fall to the bottom
what is the chlorination method in the purification of water
chlorine gas is bubbled through to kill harmful bacteria
