KRYPTON Essay, Research Paper

I am the chemical element known as Krypton. I

can also be referred as Kr. I will be telling you

about my history, my properties, my family and my

occurrence. I will also be telling you about my

uses and ores, also the analytical methods based

on me.

I received the name krypton from the Greek word

"hidden" because I was hiding for so long,

undetected. I am from a rare group of gases called

noble gases. The other noble gases are helium,

xenon, neon, argon and radon. I was discovered

in England in 1898 almost 100 years ago by Sir

William Ramsey and Morris W. Travers. They

found me in the less volatile part of inert-gas

mixture left after oxygen had been chemically

removed from a sample of air. I am about one

millionth of the earth’s atmosphere. Only about 2 x

10-8% of the weight of the earth am I. I am a

colorless, odorless and tasteless gas. My atomic

number is 36. My atomic weight is 83.80. My

melting point is -157.20°C or -251.5°F. My gas

density at 0°C is 3.749 g/liter. My valence is 0,2.

Many of my physical properties differ according to

various scientists. The outer shell of my atom is

filled with electrons in a stable structure. That is

why there is only one atom in my element. No one

yet has prepared a chemical compound for me

that is stable at room temperature. I can be

trapped in crystals of different host compounds to

form a clathrate. The radioactive isotopes of me

known to this point are 76Kr, 77Kr, 79Kr, 81Kr,

83Kr, 85Kr, 87Kr-95Kr and 97Kr. My isotopes are

produced as by-products of nuclear fission of

uranium in nuclear reactors. They can also be

formed in particle accelerator such as the

cyclotron. Until 1962, I, like other members of my

noble gas family, was thought to be chemically

inert. Even now the only well known

characteristics of my compound are diflouride,

KrF2, and its complexes. The diflouride can be

prepared by passing an electric discharge through

a 1:1 mixture of gaseous fluorine and me at -188°

C. After the reaction is complete, the reactor will

be warmed and put into a glass vessel. I arise in

the earth’s soil, through the breakdown of uranium,

but not the radioactive breakdown though. That

may be why I am very similar to another noble

gas, Xenon. Also, the mixture of stable and

radioactive isotopes of me are produced in nuclear

reactors by the slow neutron fission of uranium.

The only stable source for me is air. The content

of my gases can be detected and determined by

gas chromatography. Before scientists had these

methods of determining my content, they obtained

it by passing a gas sample through an electric

discharge tube at low pressures and analyzing the

light with a spectrometer. The principle and most

common use for me in the world is in filling electric

lamps and electronic devices of various types. I

am used to fill greenish fluorescent lights. Both

Argon and I can be used to fill lamps with light.

My radioactive 85 is used in leak testing of sealed

containers. Another use for me is continuous

measurements, determining thickness of materials,

such as paper. I hope you have learned a little bit

more about such a small element like me.

Додати в блог або на сайт

Цей текст може містити помилки.

A Free essays | Essay
5.3кб. | download | скачати

Related works:
© Усі права захищені
написати до нас