good morning or afternoon rather morning
it’s good start isn’t it now I want to
start this talk by taking a look at the
glass of water in front of you you got
one glass of water bottle of water
whatever it is just taking your hand and
look at it up close and just tell me
what you see
it’s colorless still bit featureless to
be honest boring maybe is the word
you’re using in your head right now so
what on earth are we going to talk about
for the next 15 minutes well as it
happens boring things are things that I
get interested in sometimes and in
moments of idle speculation I think
about them years and years and years ago
in one of these idle moments of
speculation I was thinking about water
in the context of this this is the pH
scale so over there pH 1 acids pH 14
alkali and I was thinking to myself the
the only thing I can think of that’s pH
7 neutral neither acid nor alkaline is
water and now you know started to think
about that I thought oh of course that
makes sense because an acid is just
defined as something that sir has a
concentration of H+ ions hydrogen nuclei
and the more you have of them the
further the lower the pH the more Oh H
minus ions you have in solution in
something hydroxide you get higher in
the pH scale so sodium hydroxide drain
cleaner is 14 pH 14 and that is an
alkali the only thing that has an equal
number of H+ and OH h minus ions is h o
h which is water obvious
it’s very neat to write it’s very neat
another neat thing about water is how it
boils at exactly 100 degrees Celsius and
freezes at exactly zero degrees Celsius
very very neat considering how messy
nature actually is and you think how is
this possible of course we’ve defined
the temperature scale using water that’s
why it’s like that you know Convention
does play its role in science and you
know I started to pull at these sort of
meat hanging threads for for my own
entertainment and what I discovered was
something actually quite disturbing and
uncomfortable water isn’t the boring
liquid that you think it is it isn’t
this sort of Placid thing in the
background it’s actually very very very
strange stuff I mean for example this
this is an iceberg as you might see and
what you’re seeing there is a solid ice
floating on liquid water they’re the
same material and this obviously is
beautiful and you’re thinking that well
what’s weird about that well the weird
thing is of course that you can see the
iceberg at all ice is a solid it should
float down to the bottom of its liquid
like everything else in chemistry but it
doesn’t it floats because when water
molecules freeze they produce large gaps
in them in the crystal structure which
means that ice is less dense and it
floats the top this is so strange
in chemistry terms that it’s kind of
mind-boggling and we don’t see it every
day in fact you’re probably used to
something like this where ice is in your
drink and you don’t notice the fact that
it’s floating and that is weird
chemistry that is so strange
this is substance that you just don’t
see the weirdness is off right now in
front of you you’ve got liquid water the
molecule h2o is very light similar like
molecules at this temperature and
pressure in this room would be gases
ammonia methane these things are gases
why’s water liquid at this temperature
it kind of makes no sense
this is a weird substance chemists are
slightly frightened frightened of
studying it but if it wasn’t so strange
and there are many many more strange
things about it if it wasn’t so strange
and we wouldn’t be here today this is a
substance that for example can flow
upwards against the force of gravity it
floats on its own liquid it makes no
sense if you all not try and understand
some of these things I mean this is not
magical it is because of certain
understood bits of science at least in
the basic sense you have to look at the
structure of a water molecule there it
is in the middle h2o
two hydrogen’s and an oxygen in the
middle and what you’re looking at is a
molecule that’s slightly bent at about
104 degrees and it’s neutral
electrically neutral it just floats
around happily being electrically
neutral but that isn’t the end of the
story of course the oxygen is ever so
slightly negative fractionally negative
and two hydrogens are ever so slightly
positive just in tens the electronic
structure so you get this slightly just
as very slight dipole change in the
electric electric poles around the water
molecule Matt means that the hydrogen of
one with its fractional positive charge
is slightly attracted to the oxygen of
another molecule and the hydrogen above
that one is attracted to this one this
is called a hydrogen bond it happens in
many many different types of molecules
that have these sorts of bonds but with
water it’s particularly special because
water can form four of these hydrogen
bonds and they’re really small
fractional charges that can come and go
as the molecules move around in a sense
they’re not that important if you if you
were to Justice or look to look at the
values of the bonding the bonds that
combine hydrogen oxygen are way stronger
than any of these bonds here but that’s
slight attraction between different
molecules in water gives it a set of
really interesting properties that
virtually nothing else has so for
example the feet the fact that water is
a liquid at room temperature and
pressure is because in liquid that all
these
bonds forming all the time and it just
takes that little bit extra energy to
transform a liquid into a gas which
means that at this temperature water is
a liquid or something like ammonia boils
at several hundred degrees below
freezing
maybe not several hundred degrees
hundred 50 or something and this also
leads to many other very interesting
properties so let me go back one one the
other thing about this is that it shows
that water loves to stick to itself and
it loves to stick to everything else
around it you know when when Newton and
the alchemists were looking for the
universal solvent they didn’t think the
water would be it but it is it dissolves
absolutely everything given enough time
you think about the Grand Canyon that’s
basically been dissolved by water over
hundreds of thousands of millions of
years water dissolves everything it
loves to stick to things but it doesn’t
like to stick to anything more but it
likes to stick to itself it’s quite a
narcissistic molecule in that respect if
you’ve ever if you’d want a glass of
water in front of you if you look at the
edges of the the surface of the water
you’ll see that they go up on the water
on the side of the bottle the same thing
happens on ponds and everything this is
a slight meniscus at the top and that’s
because water sticks to itself and at
the boundary of different more different
media let’s say water and air it’s
actually if you’re it’s actually
relatively difficult to pierce the top
of the water now you and I can do this
because we’re you know much more
powerful than the hydrogen bonds but
like insects in slight insects like pond
skaters and those kinds of things can
just float on these things and treat
them as if they’re solid surfaces and
that same property the ability for water
to stick to itself especially on very
narrow tubes imagine these bottles of
water in front of you are very very very
narrow the meniscus would be quite
pronounced it allows water to actually
flow upwards against the force of
gravity which is useful if you are a
tree and want to get water from your
roots to the crown of your leaves use of
all of us because it means that blood
can get to the
tips of a right to the top of your brain
in small capillaries in fact water is so
fundamental to life that it’s doing
multiple multiple jobs inside you and
all life that you will be able to live
without it it’s right now transporting
energy into and out of your cells it’s
creating the environment in your cells
that mean that proteins and DNA actually
function in the right way they fold into
the right shapes to do the jobs they
need to do everywhere on earth that
there’s water there is life and there is
no life on earth without water in fact
it’s often thought that life started in
water itself for 1/2 billion years ago
at the bottom of the ocean where
hydrothermal vents these cracks in the
ocean floor are sort of spewing heat
lots of energy up through the ocean
floors it’s a place where minerals and
heat sort of combine and three half
billion years ago the early ancestors to
what we now call cells would have
started to be created in those sorts of
environments and another interesting
property of water allowed for the
complexity of life that we see around us
I told you about water floating it’s a
curiosity for sure you know but it’s
also fundamental in us being here today
across the history of the earth we’ve
had many many ice ages and so that’s
there where the surface of the earth
completely freezes over and if there was
life evolving by those times and any of
those times when ice age has happened
and water froze in a let’s say normal
way in other words from the bottom up
and the bottom it’s wherever it is up to
the surface then every time there was an
ice age any microbe or life-form that
was evolving and living at the bottom of
ponds and rivers would have been
destroyed the earth would have been
sterilized pretty much every single time
there’s an ice age but because water
freezes from the top down it means that
the water underneath as something
freezes from the top down is insulated
from whatever conditions are on the set
the outside so therefore for the three a
half billion years that life has been on
this planet there’s always been liquid
water because of this fundamental
strange property of ice floating has
always been liquid water and a place for
life to continuously evolve into the
rich complexity that we see around us
today and if water can do all these
things here on earth the question you
got to ask yourself is why can’t do it
anywhere else and this is an interesting
area of discovery because we now know
there’s water on every single body in
the solar system pretty much every
single body from the from the poles of
mercury to the mountains of water ice on
Pluto has water everywhere on Enceladus
this is a moon of Saturn we recently
discovered that underneath the thick icy
crust there are oceans of water huge
oceans of water in fact they burst out
of the surface this is a picture taken
by Cassini they burst out this is a
graphic but these disciplines were
discovered by Cassini and these are
plumes of water are just flowing out we
now know of course that the oceans Ilham
Enceladus are actually warm and we also
know that they sit on rocks that’s very
similar to the conditions in which the
water on life on earth started this is
Enceladus Europa has similar conditions
which is a moon of Jupiter there are
probably other bodies on the solar
system where this happens and if you
look beyond the solar system of course
in recent decade we’ve confirmed the
existence of several thousand exoplanets
which orbit other Suns the predictions
are there are trillions of these in our
galaxy exoplanets now we don’t know how
likely is that when you get conditions
like this life will spontaneously start
we don’t know that number but what we do
know now is that the number on the other
side in other words the possibilities
for it are exponentially higher than we
knew before because there aren’t going
to be in those trillions of planets
hundreds of thousands if not millions of
planets with liquid water which is the
essentially the signature you look for
when you start to look for life
we’re just in case you don’t know what
water looks like so the thing about
water
my ideal curiosity at the beginning
which was that why is it pH 7 why is the
temperature scales so neat
we’ve already handled that one that’s
because we’ve defined these things using
water and so many other things in
science and culture all of our lives
everything is defined by water our
entire logical world is built around
water but first civilizations started
around you know coastlines and rivers
because we need it so much power and or
politics of based around water in many
respects and to be honest they are this
is that this is the substance it’s our
connection to the very first humans if
we go back to thousands of years to meet
the first humans we wouldn’t understand
what they ate what they spoke or what
the language they spoke while their
customs but we certainly understand what
they do with water and they would
understand what we do with water it’s
our connection also to anything that
might be out there because out there in
other civil I ain’t civilized far away
civilizations if they exist or even
simple fly forms they may use other
molecules to build their bodies they may
use other molecules to transfer genetic
information from one generation to the
next but I bet you it’s a very high
likelihood that they use water to make
all those things actually function so
once again lift up your glass of water
or your bottle of water and look at it
now and just tell me one more time what
do you see in that glass of water now
you
it’s good start isn’t it now I want to
start this talk by taking a look at the
glass of water in front of you you got
one glass of water bottle of water
whatever it is just taking your hand and
look at it up close and just tell me
what you see
it’s colorless still bit featureless to
be honest boring maybe is the word
you’re using in your head right now so
what on earth are we going to talk about
for the next 15 minutes well as it
happens boring things are things that I
get interested in sometimes and in
moments of idle speculation I think
about them years and years and years ago
in one of these idle moments of
speculation I was thinking about water
in the context of this this is the pH
scale so over there pH 1 acids pH 14
alkali and I was thinking to myself the
the only thing I can think of that’s pH
7 neutral neither acid nor alkaline is
water and now you know started to think
about that I thought oh of course that
makes sense because an acid is just
defined as something that sir has a
concentration of H+ ions hydrogen nuclei
and the more you have of them the
further the lower the pH the more Oh H
minus ions you have in solution in
something hydroxide you get higher in
the pH scale so sodium hydroxide drain
cleaner is 14 pH 14 and that is an
alkali the only thing that has an equal
number of H+ and OH h minus ions is h o
h which is water obvious
it’s very neat to write it’s very neat
another neat thing about water is how it
boils at exactly 100 degrees Celsius and
freezes at exactly zero degrees Celsius
very very neat considering how messy
nature actually is and you think how is
this possible of course we’ve defined
the temperature scale using water that’s
why it’s like that you know Convention
does play its role in science and you
know I started to pull at these sort of
meat hanging threads for for my own
entertainment and what I discovered was
something actually quite disturbing and
uncomfortable water isn’t the boring
liquid that you think it is it isn’t
this sort of Placid thing in the
background it’s actually very very very
strange stuff I mean for example this
this is an iceberg as you might see and
what you’re seeing there is a solid ice
floating on liquid water they’re the
same material and this obviously is
beautiful and you’re thinking that well
what’s weird about that well the weird
thing is of course that you can see the
iceberg at all ice is a solid it should
float down to the bottom of its liquid
like everything else in chemistry but it
doesn’t it floats because when water
molecules freeze they produce large gaps
in them in the crystal structure which
means that ice is less dense and it
floats the top this is so strange
in chemistry terms that it’s kind of
mind-boggling and we don’t see it every
day in fact you’re probably used to
something like this where ice is in your
drink and you don’t notice the fact that
it’s floating and that is weird
chemistry that is so strange
this is substance that you just don’t
see the weirdness is off right now in
front of you you’ve got liquid water the
molecule h2o is very light similar like
molecules at this temperature and
pressure in this room would be gases
ammonia methane these things are gases
why’s water liquid at this temperature
it kind of makes no sense
this is a weird substance chemists are
slightly frightened frightened of
studying it but if it wasn’t so strange
and there are many many more strange
things about it if it wasn’t so strange
and we wouldn’t be here today this is a
substance that for example can flow
upwards against the force of gravity it
floats on its own liquid it makes no
sense if you all not try and understand
some of these things I mean this is not
magical it is because of certain
understood bits of science at least in
the basic sense you have to look at the
structure of a water molecule there it
is in the middle h2o
two hydrogen’s and an oxygen in the
middle and what you’re looking at is a
molecule that’s slightly bent at about
104 degrees and it’s neutral
electrically neutral it just floats
around happily being electrically
neutral but that isn’t the end of the
story of course the oxygen is ever so
slightly negative fractionally negative
and two hydrogens are ever so slightly
positive just in tens the electronic
structure so you get this slightly just
as very slight dipole change in the
electric electric poles around the water
molecule Matt means that the hydrogen of
one with its fractional positive charge
is slightly attracted to the oxygen of
another molecule and the hydrogen above
that one is attracted to this one this
is called a hydrogen bond it happens in
many many different types of molecules
that have these sorts of bonds but with
water it’s particularly special because
water can form four of these hydrogen
bonds and they’re really small
fractional charges that can come and go
as the molecules move around in a sense
they’re not that important if you if you
were to Justice or look to look at the
values of the bonding the bonds that
combine hydrogen oxygen are way stronger
than any of these bonds here but that’s
slight attraction between different
molecules in water gives it a set of
really interesting properties that
virtually nothing else has so for
example the feet the fact that water is
a liquid at room temperature and
pressure is because in liquid that all
these
bonds forming all the time and it just
takes that little bit extra energy to
transform a liquid into a gas which
means that at this temperature water is
a liquid or something like ammonia boils
at several hundred degrees below
freezing
maybe not several hundred degrees
hundred 50 or something and this also
leads to many other very interesting
properties so let me go back one one the
other thing about this is that it shows
that water loves to stick to itself and
it loves to stick to everything else
around it you know when when Newton and
the alchemists were looking for the
universal solvent they didn’t think the
water would be it but it is it dissolves
absolutely everything given enough time
you think about the Grand Canyon that’s
basically been dissolved by water over
hundreds of thousands of millions of
years water dissolves everything it
loves to stick to things but it doesn’t
like to stick to anything more but it
likes to stick to itself it’s quite a
narcissistic molecule in that respect if
you’ve ever if you’d want a glass of
water in front of you if you look at the
edges of the the surface of the water
you’ll see that they go up on the water
on the side of the bottle the same thing
happens on ponds and everything this is
a slight meniscus at the top and that’s
because water sticks to itself and at
the boundary of different more different
media let’s say water and air it’s
actually if you’re it’s actually
relatively difficult to pierce the top
of the water now you and I can do this
because we’re you know much more
powerful than the hydrogen bonds but
like insects in slight insects like pond
skaters and those kinds of things can
just float on these things and treat
them as if they’re solid surfaces and
that same property the ability for water
to stick to itself especially on very
narrow tubes imagine these bottles of
water in front of you are very very very
narrow the meniscus would be quite
pronounced it allows water to actually
flow upwards against the force of
gravity which is useful if you are a
tree and want to get water from your
roots to the crown of your leaves use of
all of us because it means that blood
can get to the
tips of a right to the top of your brain
in small capillaries in fact water is so
fundamental to life that it’s doing
multiple multiple jobs inside you and
all life that you will be able to live
without it it’s right now transporting
energy into and out of your cells it’s
creating the environment in your cells
that mean that proteins and DNA actually
function in the right way they fold into
the right shapes to do the jobs they
need to do everywhere on earth that
there’s water there is life and there is
no life on earth without water in fact
it’s often thought that life started in
water itself for 1/2 billion years ago
at the bottom of the ocean where
hydrothermal vents these cracks in the
ocean floor are sort of spewing heat
lots of energy up through the ocean
floors it’s a place where minerals and
heat sort of combine and three half
billion years ago the early ancestors to
what we now call cells would have
started to be created in those sorts of
environments and another interesting
property of water allowed for the
complexity of life that we see around us
I told you about water floating it’s a
curiosity for sure you know but it’s
also fundamental in us being here today
across the history of the earth we’ve
had many many ice ages and so that’s
there where the surface of the earth
completely freezes over and if there was
life evolving by those times and any of
those times when ice age has happened
and water froze in a let’s say normal
way in other words from the bottom up
and the bottom it’s wherever it is up to
the surface then every time there was an
ice age any microbe or life-form that
was evolving and living at the bottom of
ponds and rivers would have been
destroyed the earth would have been
sterilized pretty much every single time
there’s an ice age but because water
freezes from the top down it means that
the water underneath as something
freezes from the top down is insulated
from whatever conditions are on the set
the outside so therefore for the three a
half billion years that life has been on
this planet there’s always been liquid
water because of this fundamental
strange property of ice floating has
always been liquid water and a place for
life to continuously evolve into the
rich complexity that we see around us
today and if water can do all these
things here on earth the question you
got to ask yourself is why can’t do it
anywhere else and this is an interesting
area of discovery because we now know
there’s water on every single body in
the solar system pretty much every
single body from the from the poles of
mercury to the mountains of water ice on
Pluto has water everywhere on Enceladus
this is a moon of Saturn we recently
discovered that underneath the thick icy
crust there are oceans of water huge
oceans of water in fact they burst out
of the surface this is a picture taken
by Cassini they burst out this is a
graphic but these disciplines were
discovered by Cassini and these are
plumes of water are just flowing out we
now know of course that the oceans Ilham
Enceladus are actually warm and we also
know that they sit on rocks that’s very
similar to the conditions in which the
water on life on earth started this is
Enceladus Europa has similar conditions
which is a moon of Jupiter there are
probably other bodies on the solar
system where this happens and if you
look beyond the solar system of course
in recent decade we’ve confirmed the
existence of several thousand exoplanets
which orbit other Suns the predictions
are there are trillions of these in our
galaxy exoplanets now we don’t know how
likely is that when you get conditions
like this life will spontaneously start
we don’t know that number but what we do
know now is that the number on the other
side in other words the possibilities
for it are exponentially higher than we
knew before because there aren’t going
to be in those trillions of planets
hundreds of thousands if not millions of
planets with liquid water which is the
essentially the signature you look for
when you start to look for life
we’re just in case you don’t know what
water looks like so the thing about
water
my ideal curiosity at the beginning
which was that why is it pH 7 why is the
temperature scales so neat
we’ve already handled that one that’s
because we’ve defined these things using
water and so many other things in
science and culture all of our lives
everything is defined by water our
entire logical world is built around
water but first civilizations started
around you know coastlines and rivers
because we need it so much power and or
politics of based around water in many
respects and to be honest they are this
is that this is the substance it’s our
connection to the very first humans if
we go back to thousands of years to meet
the first humans we wouldn’t understand
what they ate what they spoke or what
the language they spoke while their
customs but we certainly understand what
they do with water and they would
understand what we do with water it’s
our connection also to anything that
might be out there because out there in
other civil I ain’t civilized far away
civilizations if they exist or even
simple fly forms they may use other
molecules to build their bodies they may
use other molecules to transfer genetic
information from one generation to the
next but I bet you it’s a very high
likelihood that they use water to make
all those things actually function so
once again lift up your glass of water
or your bottle of water and look at it
now and just tell me one more time what
do you see in that glass of water now
you
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