The Chemistry of Space

7/31/2019 The Chemistry of Space

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The chemistry of space

Submitted to - submitted by-

Mrs. Simrat Kaur Harpreet Kaur


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The birth of universe Time zero for universe is the

instant at which the universe was

born.

The most pronounced feature of the

early universe was an all-encompassing flood of energy, whichwas comparable in its characteristics

to that of electromagneticradiatio s


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Electromagnetic radiation is a

form of energy propagated byperiodic fluctuations of electricand magnetic fields in space.

The most common form ofelectromagnetic radiations arelight, UV-rays, radio waves and

gamma rays, photons.


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The two most common forms ofelectromagnetic radiations present in theuniverse were gamma rays and photons.

In the universe there were also presentlarge no. of neutrinos (small particleshaving carrying no electrical charge andlittle or no mass.)

The interaction among gamma rays,photons and neutrinos resulted in theformation of first particles


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Formation of electrons

The interaction between gamma raysand neutrino (whose total energy is

no more than 0.511 MeV. ) leads tothe formation of lightest particlese.g. electron.

neutrino + gamma rays electron


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Conditions in universe immediately afterbig bang was not favorable for the

formation of electrons. At that time thegamma rays ,photons and neutrinos havevery large amount of energy, much more

than was needed to produce the electrons.

Instead conditions favored the formation

of more massive particles with largeenergy equivalents. e.g. protons and

mesons.


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Formation of protons The interaction between gamma rays

and neutrino with a total amount of

energy 1000 MeV leads to theformation of protons .

Gamma rays+ neutrino proton


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A cooling universeIn order to understand the variouschemical reactions the scientists

need to know the following

Estimates of energy present. Approximate temperature of the

universe


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Cooling of universe The temperature of universe after a

few microseconds after the big bang

is 10 K. The original fireball cooledand expanded very rapidly.

Within a few microseconds the

temperature drooped and creates anenvironment in which mesons,electrons and protons were able toform.


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Formation of

antiparticles Another category of particles was

also being created at the same time,the various forms of antimatter.

Antiparticles are identical toparticles except their charge.

Antiparticles are formed by

reactions similar to that of protons,electrons .the only difference is thatit involves antineutrino rather than

neutrino.


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Particle decay Some particles in early moments following

the big-bang were destroyed by theprocess of matter/antimatter annihilation.

Others were disappeared by otherprocesses. The most common is nuclear

instability


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Particle decay

At some point the particles spontaneouslybreaks into two or more other particles.

For example the neutrons were also formedby the interaction of protons andelectrons.

Protons + electrons neutrons


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Particle decay Bt free neutrons are inherently

unstable and decay with half-life

period of 1,013 seconds So it gives back

Neutron proton+ electron+

neutrino


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Formation of compoundparticles

The first particles formed weredispersed over a wide space. As with

explosion the force of expansion wasgreat. particles rushed outwards.

Within a matter of seconds a new force

came into being. gravitational forcewhich tends to pull the particlestowards each other.


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As the temperature decreases

,the gravitation become moresignificant than force of

expansion.It becomes possible for two

newly produced particles to benear to each other and

approach each other closely

enough to bond.


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Formation of compound

particles The first and simplest reaction was

Proton+ neutron deuteron

Deuterons were highly unstable,when struck with gamma rays

deuterons +gamma rays proton+

neutron


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As the temperature of the universedecreases the second reaction began tooccur

Deuterium+ deuterium helium+neutron

The other reaction is Deuterium+ deuterium hydrogen+

proton


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Thank you foryour patient

listening

Documents

The Chemistry of Space