A geriatric gentleman very close to me has a heart
ailment. He often suffers from bouts of
breathlessness. Medical intervention is
in progress. As part of the treatment it
was suggested that “he be given oxygen”.
Accordingly refillable “oxygen” cylinders were purchased from a
pharmacy. Each would last forty
minutes. Hence from a convenience point
of view an “oxygen machine” has been rented.
It works on electricity and supposedly releases oxygen through a mask
that the patient wears.
I was intrigued by the small cylinders and the “oxygen machine”. The machine is fairly large in size being a
box two feet wide, two feet deep and three feet high. The deposit on the machine is Rs. 5000/-and
the weekly rent is Rs. 1000/-. The cost
of renting the machine set me thinking. I
found it puzzling that so precious a thing as oxygen would cost so little. So I wore the mask to see what it felt
like. I wanted to experience what a gush
of pure oxygen entering my nostrils would feel like. I felt nothing. At the same time it was obvious that the
machine was emitting a gas through the pipe connected to the mask. Just prior to the pipe is a small bottle
containing water (I assume) through which one can see a gas escaping into the
pipe.
So I was still left with the question – how is it possible
to get a virtually interminable supply of pure oxygen, one of the most
essential elements of life, so cheaply.
And that too using a machine which seemed fairly nondescript. And how come I was not left feeling distinctly oxygenated after inhaling pure
oxygen?
So I Google’d “separating oxygen from air”. Sure enough, I found sufficient evidence to
be sure that the machine was not really emitting oxygen. Think of it – does it seem obvious to anyone
that a simple machine can simply “reach” into air around it and “extract”
oxygen? The What I learnt was that to
separate the individual gases in air, the air is first solidified by cooling well
below ice-age levels. Maybe to something like Minus 200 OC.
[Boiling point of oxygen = Minus 183 OC. Melting point of
oxygen = Minus 210 OC.
Boiling point of nitrogen =Minus 196 OC.
Melting point of oxygen = Minus 219 OC]
Let us assume that air contains oxygen and nitrogen only (in
any case these two makes most of air).
So the idea is, cool down air until it solidifies. That is around Minus 220 OC. So imagine that the air around us went that
cold. Then the air around us and in our
lungs would be solid. And
we would be frozen equivalents of Madame Tussaud’s artistic creations.
Then start warming the solid air. Warm it up to Minus 183 OC and stay there. Oxygen would boil over and start escaping as
a gas. Now send it through the tube of
the Rs. 1000/- a week machine into the mask and voila! – you are inhaling
oxygen! One look at the described machine
and you know that is not what it can do.
For that, it would at least have to be your regular fridge which has a compressor
which I instinctively knew this machine
did not. And if this machine were a
super-refrigerator, it would have to emit hot air like a fridge or an AC which
it did not. Not to mention the fact that
the Google’d information spoke about “cryogenic distillation” to separate
oxygen from air. Whoa! – that’s rocket
science – I have heard of “cryogenic rocket engine” and this Rs. 1000/- box was
not it. “Hah!” – I said to the gentleman’s
daughter – “this ain’t an oxygen machine and the gas going into his nostrils
ain’t oxygen!”. (Didn’t go down well with
the daughter at all!)
So I threw this one at my son who just got out of a year’s
grinding study of high school Chemistry (which he thoroughly despised). Well guess what … my conclusion seemed fairly
obvious to him. So I asked him if the machine
does not cryogenically distill out oxygen, what the hell does it do? We concluded after some debate that maybe it
just increases the percentage of oxygen in the air by reducing the amount of
nitrogen. Great, sounds plausible. But how does it distill out nitrogen without
the cryogenic stuff? So my son said
there are metals which “adsorb” nitrogen.
I didn’t Google that one, I just went with the assumption that no matter
how much he had hated Chemistry, something must have stuck. So we said fine let’s go with the theory that
it has a metal element which “adsorbs” nitrogen. And maybe as part of servicing the machine
that “nitrogen filter” is probably replaced because it got too “adsorbed” in nitrogen. Like what happens to an Aquaguard filter, so
very very plausible .
But yet a doubt lingers – how come now suddenly a simple
alternative was found to the cryogenic mumbo jumbo? So I decided to try and get a bit intuitive. Most of air is nitrogen. Is that the reason it is possible to “pick it
out”? Let’s say the floor of a room is
littered with tennis balls – 3000 red ones, 200 blue ones and 50 white ones. The game is to pick as many of them as possible
in 15 seconds. Just one condition – you
must pick balls of the same colour.
Obviously the red ones are the easiest to pick. Maybe that is why nitrogen is the easiest to
pick by adsorption? It sounds intuitive
to me.
The air coming out of the machine also passes through water
as mentioned earlier, so it is reasonable to assume that dust gets caught in
the water and cleaner air passes on to the patient’s nostrils.
So I conclude fairly confidently (this does not mean I am
right but I did come up with what seems like a very logical theory)
(1) The gas let out in the mask is not oxygen
(2)It is air richer in oxygen that the air surrounding us
(3)It is cleaner than the air surrounding us
In other words, the machine dispenses air that is probably
the equivalent quality as clean mountain air.
So can I say that the machine would be of no use in clean and pristine
surroundings? Possibly.
Then comes the next thought - If it requires “cryo science” to extract
oxygen from air, how come our body does it so effortlessly? Surely there is no cryogenic engine inside
us? Now this one I was able to figure
out in a jiffy. The obvious thing to do
would be to mouth platitudes along the lines of “The human body…a miracle of
nature…etc. etc. and very soon reach God and his greatness”. But let’s not use God as a cupboard to shove
in everything we can’t explain. The Church,
Temple & Mosque have been fighting that losing battle for a long time. When a fire burns it consumes oxygen but
there is no cryogenic distillation going on.
So how does it happen? That means
oxygen gets attracted to the fire, extracts itself from air and helps the fire
burn. That’s a chemical reaction. The intuitive way of looking at it is – you need
to create conditions that prompt oxygen to extract itself from air and throw
itself into a reaction. However do note
that at the end of such a reaction oxygen did not remain itself, but got converted
into something – ash or coal etc. So
when you breathe air, the act of producing energy that your body continuously performs,
attracts oxygen, combustion takes place and you are able to do what you are doing
– run, jump, walk or just exist.
So you can attract oxygen from air and entice it into burning
itself towards an end. But to extract it
from air and preserve it as oxygen takes special effort.
So what was the point of this seemingly pointless discourse? The point was my realization that I could
have figured this all out when I was in school without reading the text book or
attending classes – nothing I learnt as part of “higher education” was needed
to figure it out. But I did not figure out such things in school. In school I would have practiced drawing a
diagram of the machine, labelling its parts and describing how it gave out
oxygen to save the lives of sick people (FILL IN THE BLANKS – The machine which
is used to produce oxygen for breathing by sick people is called ________). The class I was in would have never seen the
machine and definitely would not have spent a few hours doubting its
capabilities and figuring out what is really does. But somewhere some place there must be a
school where students do it. I wonder
where it is. Because most definitely
none of the folks I spend time with – at home or at work went to such a school.
