Isotopes of chlorine

Naturally occurring isotopes of any element are present in unequal amounts. For example, chlorine exists in two isotopic forms, one with 17 protons and 18 neutrons ( Cl) and the other with 17 protons and 20 neutrons ( Cl). The isotopes are not radioactive, and they occur, respectively, in a ratio of nearly 3 1. In a mass spectrum, any compound containing one chlorine atom will have two different molecular masses (m/z values). For example, methyl chloride (CH3CI) has masses of 15 (for the CH3) plus 35 (total = 50) for one isotope of chlorine and 15 plus 37 (total = 52) for the other isotope. Since the isotopes occur in the ratio of 3 1, molecular ions of methyl chloride will show two molecular-mass peaks at m/z values of 50 and 52, with the heights of the peaks in the ratio of 3 1 (Figure 46.4). 

The two isotopes of chlorine are Cl and y3l, which occur naturally in the abundance ratio of 3 1. 

A diagrammatic illustration of the effect of an isotope pattern on a mass spectrum. The two naturally occurring isotopes of chlorine combine with a methyl group to give methyl chloride. Statistically, because their abundance ratio is 3 1, three Cl isotope atoms combine for each Cl atom. Thus, the ratio of the molecular ion peaks at m/z 50, 52 found for methyl chloride in its mass spectrum will also be in the ratio of 3 1. If nothing had been known about the structure of this compound, the appearance in its mass spectrum of two peaks at m/z 50, 52 (two mass units apart) in a ratio of 3 1 would immediately identify the compound as containing chlorine. 

How much would 0.754 mole of chlorine-35 atoms weigh How much would 0.246 mole of chlorine-37 atoms weigh What is the weight of a mole of average atoms in a mixture of the above samples What is the atomic weight of the naturally occurring mixture of these two isotopes of chlorine ... 

There are two naturally occurring isotopes of chlorine chlorine-35 and chlorine-37. The mass of an atom of chlorine-35 is 5.807 X 10-23 g and that of an atom of chlorine-37 is 6.139 X 10-23 g. In a typical natural sample of chlorine, 75.77% of the sample is chlorine-35 and 24.23% is chlorine-37. What is the molar mass of a typical sample of chlorine ... 

Another way to describe an isotope is to state its elemental name and mass number. The stable isotopes of chlorine... 

Although 28Mg is farther from the band of stability than is 27Mg, the former is an even-even nuclide while the latter is an even-odd nuclide. As we have seen earlier, even-even nuclides tend to be more stable. Consequently, the even-even effects here outweigh the fact that 28Mg is farther from the band of stability. Another interesting case is shown by considering these isotopes of chlorine ... 

Consider the transmutation—creation of one element from another— of Cl-35. This isotope of chlorine is bombarded by a neutron and H-l is created, along with an isotope of a different element. First, a partial nuclear equation is written ... 

Kratzer, A. A spectroscopic confirmation of the isotopes of chlorine. Z. f. Physik 30, 460-465... 

Obviously, there is an isotope effect on the vibrational frequency v . For het-eroatomic molecules (e.g. HC1 and DC1), infrared spectroscopy permits the experimental observation of the molecular frequencies for two isotopomers. What does one learn from the experimental observation of the diatomic molecule frequencies of HC1 and DC1 To the extent that the theoretical consequences of the Born-Oppenheimer Approximation have been correctly developed here, one can deduce the diatomic molecule force constant f from either observation and the force constant will be independent of whether HC1 or DC1 was employed and, for that matter, which isotope of chlorine corresponded to the measurement as long as the masses of the relevant isotopes are known. Thus, from the point of view of isotope effects, the study of vibrational frequencies of isotopic isomers of diatomic molecules is a study involving the confirmation of the Born-Oppenheimer Approximation. 

Hofmann AW, White WM (1982) Mantle plumes from oceanic crust. Earth Planet Sci Lett 57 421-436 Hoering TC, Parker PL (1961) The geochemistry of the stable isotopes of chlorine. Geochim Cosmochim Acta 23 186-199... 

Example To calculate the nominal mass of SnCl2, the masses of "Sn and Cl have to be used, i.e., 120 u + 2 x 35 u = 190 u. While, the Cl isotope represents the most abundant as well as the lowest mass isotope of chlorine, "Sn is the most abundant, but not the lowest mass isotope of tin which is Sn. 

ISOTOPES There are a total of 25 isotopes of chlorine. Of these, only two are stable and contribute to the natural abundance on Earth as follows Cl-35 = 75.77% and Cl-37 = 24.23%. All the other 23 isotopes are produced artificially, are radioactive, and have half-lives ranging from 20 nanoseconds to 3.01 x 10+ years. 

Fig. 8.5. The delicious cocktail of the supernovas. Mixing 13 measures of SNll with 1 measure of SNl, we find a composition of matter that approaches observed abundances in the Solar System. Certain isotopes of chlorine, potassium and scandium, among others, are not produced in snfficient qnantities, however. (From Nomoto et at. 1997.)...

The two sets of vibrational frequencies have for their origin the two isotopes of chlorine in the sample of HC1 (75% of 35Cl and 25% of 37C1). When the same transition is considered for the two molecules, reunited in the sample, only the reduced mass differs, leading to the separation. The calculation leads to ... 

Clusius and Dickel used a column 36 m long to make 99+% pure isotopes of chlorine in HCl. The cascade of Figure 19.15 has a total length of 14 m most of the annular diameter is 25.4 mm, and the annular widths range from 0.18 to 0.3 mm. The cascade is used to recover the heavy isotope of sulfur in carbon disulfide a production rate of a 90% concentrate of the heavy isotope of 0.3 g/day was achieved. 

SAMPLE SOLUTION (a) The two isotopes of chlorine are 35CI and 37CI. There will be three isotopically different forms of p-dichlorobenzene present. They have the structures shown as follows. Each one will give an M+ peak at a different value of m/z. 

The most obvious example of such behavior is for molecules which contain chlorine or bromine. The two isotopes of chlorine occur naturally in die ratio of 35C1 37C1 = 100 32.7 (3.058 1). A molecule such as chlorobenzene would... 

Of the radio-active isotopes of chlorine, only chlorine-36 could be used in polymer research. Its half-life is very long it gives /8-rays of maximum energy of 0.71 MeV and of considerably greater penetrating power than those from the isotopes just considered. The available specific activities are not very high but are adequate for the applications which can be foreseen. 

Not all of the atoms in a sample of chlorine, for example, will be identical. Some atoms of the same element can contain different numbers of neutrons and so have different nucleon numbers. Atoms of the same element which have the same proton number but different neutron numbers are called isotopes. The two isotopes of chlorine are shown in Figure 3.4 (p. 36). 

The principal isotopes of chlorine are 35C1 and 37C1. A cluster of five peaks indicates that dichlorodiphenyldichloroethane (DDE) contains four chlorines. 

The NMR properties of the halogens are given in Table 1. The isotopes of chlorine, bromine and iodine have a spin I > Vi and so possess a quadrupole moment. The technique of nuclear quadrupole resonance (NQR) will not be examined in this chapter. The T9F NMR spectra will be discussed as well as the effects of halogen on proton spectra. 

This isotope of chlorine ion has 17 protons (atomic number), 20 neutrons (mass number minus atomic number), and 18 electrons (gained one electron). 

Solution Both isotopes of chlorine have 17 protons. Chlorine-35 will have 18 neutrons to make the total mass number of 35. Chlorine-37 will have 20 neutrons to make a total mass number of 37. Multiply the masses of the two isotopes by their relative abundances ... 

In Example 2.2 (and Table 2.1) we encountered the two isotopes of chlorine. Each of these isotopes has an / value of and a substantial y value as well as an... 

The atomic mass of chlorine is 35.453 amu. Does any atom of any isotope of chlorine have a mass of 35.453 amu Explain. 

How many protons and how many neutrons are in the nddeus of the isotope of dilorine with mass 5 Of the isotope of chlorine with mass 37 Of tlie isotope of plutonium with mass 239 ... 

Using different membranes and various membrane techniques, isotopes of chlorine [155], carbon [156], lithium in aqueous solutions [157,158], and uranium in CH4 [158,159] were separated. Isotopes of gadolinium and neodymium were separated in hybrid system of nanofiltration/complexation [50]. 

Two naturally occurring isotopes of chlorine exist chlorine-35 and chlorine-36. Isotopes are two or more forms of an element. Isotopes differ... 

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