States of matter Flashcards
Solid properties
strong forces fixed positions lattice arrangement not a lot of energy only vibrate
why do solids expand when heated?
the particles are vibrating more
liquid properties
some force of attraction free to move but stay together don’t keep definite shape have same volume more energy
why do liquids expand when heated?
the particles move faster
gas properties
no force of attraction
free to move
collisions
more energy
what happens when a gas is heated?
expand or pressure increases because particles are moving faster with more energy
what is subliming?
when a solid changes straight to a gas
what happens during chemical reactions?
bonds between atoms break and change places
what can you use to measure melting point?
melting point apparatus
water bath
thermometer
what is simple distillation used for?
separating a liquid from a solution
what is the problem with simple distillation?
it only separates things that have different boiling points
what does fractional distillation do?
Separate a mixture of liquids
what is filtration used for?
separating an insoluble solid from a liquid
what does crystallisation do?
separates a soluble solid from a solution
what is chromatography used for?
separating a mixture of soluble solutions
what is mobile phase?
where the molecules can move
stationary phase
where the molecules can’t move
in paper chromatography what is the mobile phase?
the solvent
what happens if a solvent doesn’t move?
it means it is insoluble
what two things does the amount of time the molecule spends in each phase depend on?
how soluble they are in the solvent
how attracted they are to the stationary phase
what happens to molecules with a higher solubility?
spend more time in the mobile phase so will be carried further up paper
what chemical do you use to show the colour of the solvent?
locating agent
what is a Rf value?
ratio between the distance travelled by the dissolved solute and the distance travelled by the solvent
how to calculate Rf value?
distance travelled by solute divided by distance traveled by solvent
what are the three sources of water?
surface water
ground water
waste water
surface water
from lakes and rivers
ground water
from rocks that trap water underground
waste water
water that’s been contaminated by human waste
How to purify water
filtration
sedimentation
chlorination
sedimentation
sulfate is added to make particles clump and sink to bottom
chlorination
chlorine gas is bubbles through to kill harmful bacteria
disadvantages of distillation
needs lots of energy
really expensive
what is deionised water?
water that has had ions from normal water present but removed
