Isotopes :
Atoms of a given element, have the same atomic number, that is they contain the same number of protons. However, they may contain different numbers of neutrons. They correspond to the same element and are chemically indistinguishable; they have different mass numbers
(Iso means same, tope means same place; they occupy the same place in the periodic table).
Therefore atoms of the same element having same number of protons
(atomic number but different number of neutrons (different mass numbers), are called isotopes. Isotopes may be naturally occurring or artificially made.
(atomic number but different number of neutrons (different mass numbers), are called isotopes. Isotopes may be naturally occurring or artificially made.
Example : Normal hydrogen (protium) 1H1 deuterium 1H2 and tritium 1H3 are the isotopes of hydrogen. 6C11, 6C12 and 6C14 are the isotopes of carbon. Uranium has two isotopes namely 92U235 and 92U238.
Radio-istopes : The term radio-isotope is the shortened from of radioactive isotope. If the isotope of an element is radioactive, then the isotope is called. radio-isotope, referred to as radio-nuclide. At least one radio-isotope of every element is available. Over a thousand of them can be made artificially, mostly in nuclear reactors using slow neutrons as bombarding particles.
Examples : Cobalt-60 an isotope of cobalt is radioactive; It is usually refereed to as radio-cobalt. Radio-iodine (I131), radio-iron (Fe59) radio-sodium (Na24), radio-phosphorous (P30), radio-cobalt (Co60), radio-sulphur (S35) and radio-carbon (C14) are some of the radio-isotopes.
Uses of Radio – Isotopes : Radio-isotopes find applications is various fields, some are listed below.
Radio-phosphorous is used in agriculture to determine the kind of phosphate required for a given soil and crop.
Radio-iodine is used in the treatment of overactive thyroid glands and radio-cobalt in the treatment of cancer, Radio-sodium is used to study the action of medicines.
Radio-cobalt or radio-iridium is used in industry to check machine parts.
Radio-carbon is used to estimate the age of fossils and archaeological specimens.
POINTS TO REMEMBER
Spontaneous disintegration of certain unstable atomic nuclei with the emission of certain radiations is called radioactivity.
Becquerel rays are the radiations emitted by radioactive elements.
The elements from atomic number 81 to 92 are found to be radioactive.
The radioactive radiations are alpha (alpha) particles, beta (beta) rays and gamma (Gama) radiations.
(alpha) - particles are nothing but helium nuclei,
- rays are stream of electrons and
- radiations are high energy photons.
The changing of one element into another is known as transmutation. Original atom is parent atom and the new atom produced is the daughter atom.
- rays are stream of electrons and
- radiations are high energy photons.
The changing of one element into another is known as transmutation. Original atom is parent atom and the new atom produced is the daughter atom.
Half life of a radioactive element is the time taken by a radioactive sample of that element, to get reduced to half its mass.
Half life varies from microseconds to billions of years.
The phenomenon by which radioactivity is induced in an element, is called Induced radioactivity or artificial
radioactivity.
When a stable aluminum atom is bombarded by (alpha) particles it becomes radio phosphorus.
Atoms of the same element having same number of protons (atomic number) but different number of neutrons (different mass number) are called isotopes.
Isotopes of Hydrogen are Normal Hydrogen (protium) (1H1), Deuterium (1H2) and Tritium (1H3)
Isotopes of Carbon are 6C11, 6C13, and 6C16,
Isotopes of Uranium are 92U235 and 92U238
It the isotope of an element is radioactive, then the isotope is called radio isotope, referred to as radio nuclide. Radio nuclides are manufactured in nuclear reactors.
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