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Isotopes of potassium

Seventeen isotopes of potassium are known. Ordinary potassium is composed of three isotopes, one of which is 40oK (0.0118%), a radioactive isotope with a half-life of 1.28 x IO9 years. [Pg.46]

The radioactive, naturally occurring isotope of potassium——decays by emission... [Pg.263]

ISOTOPES A total of 18 isotopes of potassium have been discovered so far. Just two of them are stable K-39 makes up 93.2581% of potassium found in the Earth s crust, and K-41 makes up 6.7301% of the remainder of potassium found on Earth. All the other 16 potassium isotopes are unstable and radioactive with relatively short half-lives, and as they decay, they produce beta particles. The exception is K-40, which has a half-life of 1.25x10 years. [Pg.53]

The salt used in this experiment is potassium chloride (KC1). Potassium-40 is a naturally-occurring isotope of potassium (abundance = 0.0117%) whose half life is 1.28 x 109 years. It emits a gamma ray at 1.461 MeV with a decay fraction of 10.7%, in addition to beta particles with a decay fraction of 89.3%. The decay scheme for 40K is given in Fig. 3.1. A tared container (see Experiment 2) is filled with solid KC1, closed, weighed, and counted. [Pg.32]

This experiment examines the self-absorption of the beta particles emitted by 40K (t1/2 = 1.28 x 109 a, Emax = 1.311 MeV, 89.3%), a naturally-occurring isotope of potassium (abundance = 0.0117%), in potassium chloride (KC1) salt. The degree of beta-particle self-absorption (including self-scattering) depends on the energy of the beta particles, the sample matrix elemental... [Pg.35]

There are three naturally occurring isotopes of potassium potassium-39, potassium-40, and potassium-41. Potassium-40 is radioactive. Isotopes are two or more forms of an element. Isotopes differ from each other according to their mass number. The number written to the right of the element s name is the mass number. The mass number represents the number of protons plus neutrons in the nucleus of an atom of the element. The number of protons determines the element, but the number of neutrons in the atom of any one element can vary. Each variation is an isotope. [Pg.454]

Eighteen artificial radioactive isotopes of potassium with measured half lives are known also. A radioactive isotope is one that breaks apart and gives off some form of radiation. Artificially radioactive isotopes are produced when very small particles are fired at atoms. These particles stick in the atoms and make them radioactive. [Pg.454]

Step 1. The mass number of this isotope of potassium is 40. Therefore the sum of the mass number of the products must also be 40, and must have a mass number of 40. [Pg.273]

The two isotopes of potassium with significant abundance in nature are (isotopic mass 38.9637 amu, 93.258%) and K (isotopic mass 40.9618 amu, 6.730%). Fluorine has only one naturally occurring isotope, F (isotopic mass 18.9984 amu). Calculate the formula mass of potassium fluoride. [Pg.67]

Ans. A radioactive isotope of potassium, K, is a positron emitter, and the nuclear reaction for the... [Pg.189]

The most abundant isotope of potassium is (93.1%), with also a stable isotope (6.8%), but there is a naturally occurring radioactive isotope (0.11%). [Pg.222]

Although naturally occurring potassium consists mostly of the isotope of mass number 39 (93.25%), isotopes of mass number 41 (6.73%) and 40 (0.01%) also are present. Write the nuclear symbol for each of the isotopes of potassium. How many neutrons are present in each isotope Is the average atomic mass of potassium (39.10 g) consistent with the relative abundances of the isotopes ... [Pg.635]

Potassium ion is present in foods and is an essential nutrient in the human body. One of the naturally occurring isotopes of potassium, potassium-40, is radioactive. Potassium-40 has a natural abundance of 0.0117% and a half-life ti/2 = 1.28 X 10 yr. It undergoes radioactive decay in three ways 98.2% is by electron capture, 1.35% is by beta emission, and 0.49% is by positron emission, (a) Why should we expect to be radioactive (b) Write the nuclear equations for the three modes by which decays, (c) How many °K ions are present in 1.00 g of KCl (d) How long does it take for 1.00% of the K in a sample to undergo radioactive decay ... [Pg.907]

Myers WD, Swiatecki WJ (1966) Nuclear masses and deformations. Nucl Phys 81 1 Neuilly M, Bussac J, Frejaques C et al (1972) Sur Fexis-tence dans un passe recule d une reaction en chaine natureUe de fissions, dans le gisement d uranium d Oklo (Gabon). Compt Rend D 275 1847 Nier AO (1935) Evidence for the existence of an isotope of potassium of mass 40. Phys Rev 48 283 Nier AO (1938) Variations in the relative abundances of the isotopes of common lead from various sources. J Am Chem Soc 60 1571... [Pg.34]

R. Gupta, W. Happer, L. Lam, S. Svanberg Hyperfine structure measurements of excited S states of the stable isotopes of potassium, rubidium and cesium by cascade radio-frequency spectroscopy. Phys. Rev. A8, 2792 (1973)... [Pg.366]

An alternative approach is to measure the total body content of potassium again, fat contains no potassium, which occurs only in the fat-free mass of the body. There is a gender difference here in males the fat-free mass contains 60 mmol potassium/kg, and in females 66 mmol/kg. The radioactive isotope of potassium, occurs naturally. [Pg.177]

CI.34 is an electrolyte required by the human body and found in many foods as well as salt substitutes. One of the isotopes of potassium is potassium-40, which has a natural abundance of 0.012% and a half-life of 1.30 X 10 y. The isotope potassium-40 decays to calcium-40 or to argon-40. A typical activity for potassium-40 is 7.0 p,Ci per gram. (16.2, 16.3, 16.4)... [Pg.593]


See other pages where Isotopes of potassium is mentioned: [Pg.94]    [Pg.57]    [Pg.75]    [Pg.18]    [Pg.50]    [Pg.304]    [Pg.306]    [Pg.398]    [Pg.406]    [Pg.188]    [Pg.406]    [Pg.522]    [Pg.94]    [Pg.323]    [Pg.786]    [Pg.522]    [Pg.507]    [Pg.325]    [Pg.468]    [Pg.1371]    [Pg.209]    [Pg.63]   
See also in sourсe #XX -- [ Pg.51 ]

See also in sourсe #XX -- [ Pg.51 ]

See also in sourсe #XX -- [ Pg.13 ]




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Potassium isotopic

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