Noble gases in the periodic table

Several metals that are farther removed from the noble gases in the periodic table form positive ions. These include the transition metals in Groups 3 to 12 and the post-transition metals in Groups 13 to 15. The cations formed by these metals typically have charges of +1, +2, or +3 and ordinarily do not have noble-gas structures. We will postpone to Chapter 4 a general discussion of the specific charges of cations formed by these metals. 

Nobte Gssgs The noble gases, also known as the Group 18 elements, are all rather unreactive. As you will read, the reason for this low reactivity also accounts for the special place occupied by the noble gases in the periodic table. 

Ramsay, Sir William (1852-1916) Scottish physical chemist who isolated the five elements argon, neon, krypton, xenon, and radon, constituting the whole class of the noble, or inert, gases in the periodic table. He was also the first to isolate helium, previously believed to exist only in the Sun. His writings include The Gases of the Atmosphere and Elements and Electrons. He was awarded the Nobel Prize in chemistry in 1904. Radon s atomic weight was determined by Ramsay. 

The application of the foregoing routes has led to the preparation and characterization of fluorides of virtually every element in the periodic table except the three lightest noble gases, Fie, Ne and Ar. The structures, bonding, reactivity, and industrial applications of these compounds will be found in the treatment of the individual elements and it is an instructive exercise to gather this information together in the form of comparative tables. 

The noble gases, located at the end of each period, have electron configurations of the type ns2np6, where n represents the number of the outermost shell. Also, n is the number of the period in the periodic table in which the element is found. 

B Main group elements are in the A families, while transition elements are in the B families. Metals, nonmetals, metalloids, and noble gases are color coded in the periodic table inside the front cover. 

A correlation begins with the hypothesis that for a property such as boiling point, within a certain population such as the noble gases, and using the period of the element in the periodic table as the predictor, the appropriate correlation function is of the form... 

We ll see a quantitative way to decide which element is more cationlike and which is more anionlike in Section 7.4 but will note for now that it s usually possible to decide by looking at the relative positions of the elements in the periodic table. The farther left and toward the bottom of the periodic table an element occurs, the more likely it is to be cationlike the farther right and toward the top an element occurs (except for the noble gases), the more likely it is to be anionlike. 

Radon, the heaviest of the noble gases, has been much publicized in recent years because of a fear that low-level exposures increase the risk of cancer. Like astatine and francium, its neighbors in the periodic table, radon is a radioactive element with only a minute natural abundance. It is produced by radioactive decay of the radium present in small amounts in many granitic rocks, and it can slowly seep into basements, where it remains unless vented. If breathed into the lungs, it can cause radiation damage. 

Hydrogen is the most abundant element in the universe, and oxygen is the most abundant element on the earth s surface. When chemically combined, they yield water, perhaps the most important and familiar of all chemical compounds. Hydrogen combines with every element in the periodic table except the noble gases and forms more compounds than any other element. Industrially, large amounts of elemental hydrogen are produced for use in the synthesis of such chemicals as ammonia and... 

The Group 18 elements in the periodic table are currently called the noble gases. In the past, however, they were referred to as the inert gases. They were believed to be totally unreactive. Scientists have found that this is not true. Some of them can be made to react with reactive elements, such as fluorine, under the proper conditions. In 1962, the synthesis of the first compound that contained a noble gas was reported. Since then, a number of noble gas compounds have been prepared, mostly from xenon. A few compounds of krypton, radon, and argon have also been prepared. 

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