practicals paper one Flashcards
(33 cards)
simple distalation methods
-heat up mixture->liquid that evaporates rises to top pressure will force it down condensor
-bc of cold water pumping thru water jacket vapour will cool and condense into liquid form
-liquid down pipe and into beaker
simple distalation equipment
flask
bunsen burner
bung
condenser
water jacket
beaker
what does simple distalation seperate
liquid from solution
eg pute water from sea water
fractional distalation steps
-heat mixture to the degrees of substance w lowest boiling point
-that will evaporate->rise up fractioning column->thru condensor->liquid->beaker
-repeat w other substances in mixture
in fractionainal distalation what would happen if ither substances evaporated along with another one
when they get to the glass rods they would condense back into liquid because there cooler then there boiling point
filterisation
use filter paper in a funnel
poor liquif thru
solid left behind
crystalisation steps
1.heat w water bath
2.once some solvent evaporated nd can see crystals stop heating
3.leave to cool
4.ss solution cools more cyrysald will form
5.filter out crystals
6.dry crystals
crystalisation equipment
evaporationing dish
eater bath
why di u use a water bath with crystalisation
bv the solids r more susceptible to thermal decomposition
why does elctrolyte have to be ipnic compounf
because ions are free to move
soluble electrolytes
copper sulfate
dissolve it in water
insoluble electrolytes
lead bromide
melt it
molten liquid
electrolysis equipment
electrodes-anode and cathode
beaker
power supply eg battery
wires
why do u need power supply in electrolysis
drive the flow of electrons
why do u need wires in electrolysis
electrons can flow between them
what happens at anode with lead bromid
bromine becomes discharged-> lose charge
bromine becomes neutral atom
bromine will pair up and turn into bromine gas
what happens at cathode with lead bromide
lead becomes neurtal atoms bc it discharges
lead fall to bottom and create layet of molten lead
transportatioj of elevtrons lead bronide
electrons from bromid ipns being passed to positive anode and being transported along wite to the cathode using power supply then those electrons given to the lead ion turning it into atom
bromine half equation
2br- -> br2+2e-
lead half equation
pb2+ + 2e- ->pb
in aqueos solutions where do the other ipns come from
water
hydroxide and hydrogen
rules for cathode
aqueos
ion thats from least reactive element will be discharged
rules for anode
aqueos
if hallide present then thete be discharged
if no hallide presnt then hydroxide will be discharged
