chromatography
methods :
draw a line near the bottom of the filter paper in pencil
place the dyes on the paper
place the paper in a beaker of solvent (water) below the start line
*
place a lid on top of the container to stop the solvent evaporating
the solvent seeps up the paper carrying the soluable dyes with it
when the solvent has nearly dried ,
take it out and let it dry
once dry ,
mark the solvent front
calculating Re values
distance for solute : measure from the
baseline to the middle of the spot
Rf =
distance traveled by solute
distance traveled by solvent
distance for solvent : measure from the
baseline to the solvent front
Simple Distillation Elements :
used for separating ~
consists of only one type of
thermometer
liquid
·
a from a is atom
. Vapour
2
cooled and
solution ↓ ↓
water condenses both elements
it can only be used Out
&
Compounds
condenser
to separate things
~ :
with very different ~
a substance made of two on
boiling points t more different elements that ar
Un ·
Chemically bonded together
sava
water C Carbon
o O
dioxide
·
remaining
solution left Mixture :
1 the solution is in flaSk
.
~
a substance made of two or
heated and the one
more different elements that are
. condensed
3
with the lowest bpt
·
-
heat NOT chemically bonded
water collected
evaporates
pure distilled
here water
Chemical tests Carbonates
Metal Ions (cations Metal Hydroxide (w NaOH) Carbonate + acid > -
carbon dioxide + wat
**
COz (s)
+ 2H* (a) >
-
CO2(g) +
H20(
Lithium (Lit) Cu2
+
ensure Copper (11) ,
Calcium (cat) that the Cu2" coal +
201 gas
> (U
-
(OH) 2 (s)
sulphates barium
Sodium (Nat) platinum Iron (11) ,
Feat barium ions + sulphate ions >
-
sulphate
Copper (Cu2t) wire is Fe +
20H >
-
Fe(OH)2 Bad(aal +
50p
*
>
-
BaSOncs
(a) al (s) (aq)
Potassium (K") clean Iron (111) ,
Fest white precipitate of Basoy means that the
by dipping Fe3 (a) +
20M aal-Fe(OH)3 Is
Original substance was a sulphate
it in dilute HCL so that no
other substance interferes Halides
add dilute Nitric acid (HNOs) them by
Tests for gases and water Silver Mittric Solution (AgNOz)
, Chloride
"
Chlorine : bleaches damp blue litmus paper white Ag coal
+
Clinal
-
>
AgC)(s)
Oxygen :
Oxygen relights a glowing splint bromide
Carbon dioxide : turns limewater cloudy Ag" (aa)
+ Bir jaq) >
-
AgBr(s)
hydrogen :
'squeaky pop' with a lit splint iodide
Ammonia : turns damp red litmus paper blue Ag" caas +
1(aa) >
-
Aglis
Structure and Bonding
lonic bonding
Pp2
+
Feat
+ *
Ag hydrogen : H Ammonium :
NHp Nitrate :
NOz
2n2 COS
+
Cu2 Fe3 ,*
+ +
hydroxide : OH Carbonate . Sulfate : So
Ionic
Compounds
When
·
a metal and non-metal react ,
the metal atom loses an electron to form a
positive ion (cation) and the non-metal atom gains an electron to form a
negative
ion lanion) -
for group 1 and 7
the oppositely charged) ions strongly attracted by electrostatic
·
are forces of
attraction
- an ionic bond
lonic compounds -
Lattice structure
compounds with Ionic bonding ALWAYS have a giant ionic structure
they are closely packed together in a 3D lattice arrangement by the
attraction between oppositely charged ions
-
ionic compounds have : they are unable to conduct electricity when solid,
high melting points However
, they can if they are molten or
aqueous
as their ions are free move and charge
·
high boiling points to
carry
covalent Bonding
covalent bonding occurs between two non-metals and is when atoms share pairs of electron
4 each covalent bond provides one extra shared electron for each atom
-
there is a strong electrostatic attraction between the negatively charged electrons and the
positive nuclei of the atoms involved
simple molecular substances
-
atoms within a molecule are held together by strong covalent bonds
-
the forces of attraction between these molecules ,
however , are very weak
↳) the melting and boiling points are very low as the molecules are separated easily
the melting and boiling points of simple molecular substances increase as the Mr increases
-
-
most molecular substances are gases or liquids at rep /or an easily mented solid)
Giant covalent substances
all atoms are bonded together by lots of strong covalent bonds which take a lot of energy
-
-
giant covalent structures are solids with very high meeting and boiling points
-
they do Not conduct electricity -
even when molten (except graphite
-usually insolvable in water
methods :
draw a line near the bottom of the filter paper in pencil
place the dyes on the paper
place the paper in a beaker of solvent (water) below the start line
*
place a lid on top of the container to stop the solvent evaporating
the solvent seeps up the paper carrying the soluable dyes with it
when the solvent has nearly dried ,
take it out and let it dry
once dry ,
mark the solvent front
calculating Re values
distance for solute : measure from the
baseline to the middle of the spot
Rf =
distance traveled by solute
distance traveled by solvent
distance for solvent : measure from the
baseline to the solvent front
Simple Distillation Elements :
used for separating ~
consists of only one type of
thermometer
liquid
·
a from a is atom
. Vapour
2
cooled and
solution ↓ ↓
water condenses both elements
it can only be used Out
&
Compounds
condenser
to separate things
~ :
with very different ~
a substance made of two on
boiling points t more different elements that ar
Un ·
Chemically bonded together
sava
water C Carbon
o O
dioxide
·
remaining
solution left Mixture :
1 the solution is in flaSk
.
~
a substance made of two or
heated and the one
more different elements that are
. condensed
3
with the lowest bpt
·
-
heat NOT chemically bonded
water collected
evaporates
pure distilled
here water
Chemical tests Carbonates
Metal Ions (cations Metal Hydroxide (w NaOH) Carbonate + acid > -
carbon dioxide + wat
**
COz (s)
+ 2H* (a) >
-
CO2(g) +
H20(
Lithium (Lit) Cu2
+
ensure Copper (11) ,
Calcium (cat) that the Cu2" coal +
201 gas
> (U
-
(OH) 2 (s)
sulphates barium
Sodium (Nat) platinum Iron (11) ,
Feat barium ions + sulphate ions >
-
sulphate
Copper (Cu2t) wire is Fe +
20H >
-
Fe(OH)2 Bad(aal +
50p
*
>
-
BaSOncs
(a) al (s) (aq)
Potassium (K") clean Iron (111) ,
Fest white precipitate of Basoy means that the
by dipping Fe3 (a) +
20M aal-Fe(OH)3 Is
Original substance was a sulphate
it in dilute HCL so that no
other substance interferes Halides
add dilute Nitric acid (HNOs) them by
Tests for gases and water Silver Mittric Solution (AgNOz)
, Chloride
"
Chlorine : bleaches damp blue litmus paper white Ag coal
+
Clinal
-
>
AgC)(s)
Oxygen :
Oxygen relights a glowing splint bromide
Carbon dioxide : turns limewater cloudy Ag" (aa)
+ Bir jaq) >
-
AgBr(s)
hydrogen :
'squeaky pop' with a lit splint iodide
Ammonia : turns damp red litmus paper blue Ag" caas +
1(aa) >
-
Aglis
Structure and Bonding
lonic bonding
Pp2
+
Feat
+ *
Ag hydrogen : H Ammonium :
NHp Nitrate :
NOz
2n2 COS
+
Cu2 Fe3 ,*
+ +
hydroxide : OH Carbonate . Sulfate : So
Ionic
Compounds
When
·
a metal and non-metal react ,
the metal atom loses an electron to form a
positive ion (cation) and the non-metal atom gains an electron to form a
negative
ion lanion) -
for group 1 and 7
the oppositely charged) ions strongly attracted by electrostatic
·
are forces of
attraction
- an ionic bond
lonic compounds -
Lattice structure
compounds with Ionic bonding ALWAYS have a giant ionic structure
they are closely packed together in a 3D lattice arrangement by the
attraction between oppositely charged ions
-
ionic compounds have : they are unable to conduct electricity when solid,
high melting points However
, they can if they are molten or
aqueous
as their ions are free move and charge
·
high boiling points to
carry
covalent Bonding
covalent bonding occurs between two non-metals and is when atoms share pairs of electron
4 each covalent bond provides one extra shared electron for each atom
-
there is a strong electrostatic attraction between the negatively charged electrons and the
positive nuclei of the atoms involved
simple molecular substances
-
atoms within a molecule are held together by strong covalent bonds
-
the forces of attraction between these molecules ,
however , are very weak
↳) the melting and boiling points are very low as the molecules are separated easily
the melting and boiling points of simple molecular substances increase as the Mr increases
-
-
most molecular substances are gases or liquids at rep /or an easily mented solid)
Giant covalent substances
all atoms are bonded together by lots of strong covalent bonds which take a lot of energy
-
-
giant covalent structures are solids with very high meeting and boiling points
-
they do Not conduct electricity -
even when molten (except graphite
-usually insolvable in water
