Therefore, isotopes have similar chemical properties but different physical properties. Radioisotopes, radionuclides, and radioactive nuclides are all terms used to describe radioactive isotopes. At least one radioactive isotope exists for each chemical element.
Hydrogen, for example, has three isotopes with mass numbers 1, 2, and 3, with tritium being radioactive and the other two being stable. There are about 1, radioactive isotopes of the elements known, with 50 of them occurring naturally and the rest being created artificially as direct products of nuclear processes or as radioactive descendants of these products. The half-life of a substance is the time it takes for its radioactivity to decline to half of its original value.
Applications of Isotopes Medical Field: Cobalt is a radiation source used in medicine to slow the progression of cancer. Other radioactive isotopes are employed as tracers in metabolic research and for diagnostic purposes. In a breath test, carbon is utilised to detect the ulcer-causing bacteria Heliobacter pylori. Industry: Radioactive isotopes are employed in industry to measure the thickness of metal or plastic sheets, with the strength of the radiations that penetrate the substance being investigated indicating the precise thickness.
They can also be utilised as small electrical power sources. Plutonium in spacecraft is an example. Sample Questions Question 1: Define mass number and atomic number. Answer: The number of protons that a chemical element has in its nucleus is called its atomic number. Question 2: What are isotopes and isobars?
Answer: Isotope is a variant of an element where the variant will have equal number of protons but would differ in the number of neutrons of the atom. Isobars are atoms that have same number of nucleons. Isobars of different chemical elements have different atomic number but have the same mass number. Aug 27, Explanation: To a first approximation, the chemistry of an element depends on the exchange and sharing of electrons between atoms to make and break strong chemical bonds.
Is this clear? Related questions How would you find the atomic number, atomic mass, protons, neutrons and electrons for ions and Question f36d4. The properties of an element are determined by the number of protons in its nucleus. Isotopes are atoms of the same element. They have the same atomic number but different mass number. Number of protons and electrons in isotopes are the same.
So, since the number of protons are the same and since protons determine the chemical properties of an atom, they show similar chemical properties. Most hydrogen atoms have just one proton, one electron, and lack a neutron. These atoms are just called hydrogen. Some hydrogen atoms have one neutron as well. These atoms are the isotope named deuterium. Other hydrogen atoms have two neutrons.
These atoms are the isotope named tritium. For most elements other than hydrogen, isotopes are named for their mass number. These atoms are the isotope called carbon A lithium atom contains 3 protons in its nucleus irrespective of the number of neutrons or electrons. Notice that because the lithium atom always has 3 protons, the atomic number for lithium is always 3.
The mass number, however, is 6 in the isotope with 3 neutrons, and 7 in the isotope with 4 neutrons. In nature, only certain isotopes exist. For instance, lithium exists as an isotope with 3 neutrons, and as an isotope with 4 neutrons, but it doesn't exist as an isotope with 2 neutrons or as an isotope with 5 neutrons.
Atoms need a certain ratio of neutrons to protons to have a stable nucleus. Having too many or too few neutrons relative to protons results in an unstable, or radioactive, nucleus that will sooner or later break down to a more stable form. This process is called radioactive decay.
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