fluorine
I’m cool because of
the refrigerant which
is a
hydrochlorofluorocar
bon (HCFC) in the
pipes at the back
NaF is added to
toothpaste to strengthen
tooth enamel and prevent
decay.
But ..
I am so reactive
that I react with
any container I am
put in. I have to
be made (by
electrolysis) as I
am needed at the
chemical plant and
used straight away.
PTFE or poly (tetrafluoroethene) is
used to coat non-stick pans
fluorine
F
F
Fluorine is the most abundant halogen in the earth along with
chlorine. It is always found in a compound. It has a low melting point
and boiling point, the lowest of the halogens. This is because the
instantaneous dipole-induced dipole bonds are weak due to F2 having
less electrons than any other halogen molecules. It is a pale yellow
gas. Fluorine is the most electronegative element of all. It is the
most reactive halogen, reactivity decreases down the group and
fluorine is at the top of the group. It will always have the oxidation
state -1. This means that in FCl, fluorine is -1 and chlorine is +1.
chlorine
PVC or poly(vinylchloride)
needs chlorine for its
manufacture
I am often made at the plant where brine is
electrolysed to cut down on the transport of
chlorine. Both reactants are products of the
electrolysis.
2NaOH + Cl2  NaCl + NaClO + H2O
I’m glad this swimming
pool has a small amount of
chlorine in to kill bacteria!
CFCs (chlorofluorocarbons) are banned
now but they are still destroying the
ozone layer.
chlorine
Chlorine is the most abundant halogen in the earth along with
chlorine. It is always found in a compound. It has a low melting point
and boiling point, second lowest to fluorine. This is because the
instantaneous dipole-induced dipole bonds are weak due to Cl2 having
less electrons than bromine and iodine molecules. It is a pale green
gas. It is the second most reactive halogen since reactivity
decreases down the group. It will usually have the oxidation state -1.
Exceptions are when bonded to F (always -1) or O (would be -2).
bromine


Tanker is lead lined and
has a cage for
protection
I have protective
clothing and breathing
apparatus
Bromomethane is a
pesticide. They are trying
to ban it because it
destroys the ozone layer
Bromine is used in the
manufacture of
medicines.
I’m so glad that this
sofa has a flame
retardant manufactured
using bromine.
bromine
Bromine is always found in a compound. It has a low melting point and
boiling point although higher than fluorine and chlorine. This is
because the instantaneous dipole-induced dipole bonds are weak but
Br2 has more electrons than chlorine and fluorine. It is a dark red
volatile liquid. It is the third most reactive halogen since reactivity
decreases down the group. It will usually have the oxidation state -1.
Exceptions are when bonded to F or Cl (always -1) or O (would be -2).
Iodine is safest to transport
because it is a solid
Iodine can be
manufactured from
sea weed.
We need iodine in our
diet to remain healthy.
It comes from vegetables
grown in soil containing
iodide ions.
I’m used
in the
manufactu
re of
medicines
Swab the patient with the
antiseptic iodine solution.
iodine
Iodine is always found in a compound. Its melting and boiling point
are higher than fluorine, chlorine or bromine. This is because the
instantaneous dipole-induced dipole bonds are stronger (it has more
electrons). It is a shiny black solid and if you heat it up it sublimes to
form a purple vapour. It is the fourth most reactive halogen since
reactivity decreases down the group. It will usually have the
oxidation state -1. Exceptions are when bonded to F, Cl or Br (always
-1) or O (would be -2).