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Isotopes

Isotopes are the same chemical elements with varying numbers of neutrons. Each isotope of a particular element has the same number of protons and electrons. Each isotope will have a different mass which corresponds to the number of neutrons present.

Lets look at the example of carbon isotopes. Carbon-12, carbon-13 and carbon-14 are isotopes of carbon with masses of 12, 13 and 14 g/mol respectively. The "normal" atomic number of carbon is 6. This means that every carbon atom has 6 protons. Therefore, the numbers of neutrons in the isotopes are 6, 7 and 8 respectively.

Isotopes have specific notation to indicate the number of neutrons. The chemical symbol is used with the number of neutrons as a superscript in the left upper corner of the chemical symbol and the atomic number as a subscript on the left lower corner of the chemical symbol.

For obvious reasons, if an element has a stable isotope(s) those isotope(s) are predominately the most abundant found on Earth and the solar system. There are only three types of elements where this is not true, tellurium, indium and rhenium. Those three isotopes are more readily found in there radioactive form.

Atomic Arrangements of Permanent Magnets

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Energy: Laser Fusion

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Radioactive Nuclei.

I'm not sure my answer is right. 7. A sample of a radioactive isotope is found to have an activity of 115 Bq immediately after it is pulled from the reactor that formed it. Its activity 2 hours and 15 minutes later is measured to be 85.2 Bq. (a) Calculate the decay constant and the half-life of the sample. (b) How many radioa

Problems for Medical Radiation

Please view the attached file to see the questions. There are diagrams and charts associated with the questions so I was unable to type them out.

Half-Life of 14-Carbon Isotope

The activity of a 1 gram carbon sample of a living organism is 0.23Bq. A 1-gram carbon sample from a fossil has an activity of 0.07Bq. The half-life of 14-carbon isotope is 5730 years. How old is the sample?

Nuclear Medicine: Determining Mass of Isotope

One of the many isotopes used in cancer treatment is (198-atomic mass)Au, with a half-life of 2.70 days. Determine the mass of this isotope that is required to give an activity of (227-atomic mass) Ci.

Nuclear radii, binding energy, isotope, uranium, fission, fusion

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Chernobyl products half life analysis

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Energy Released by Fusion

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Nuclear Physics Calculations

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Radioactivity; Activity and Half-life

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Atomic Physics Question

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Activities of Radionuclides

A radioactive sample consists of a mixture of S-35 and P-32. Initially, 5% of the activity is due to the S-35 and 95% due to the P-32. At what subsequent time will the activities of the two radionuclides in the sample be equal?

Topics in Physics

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rms (root mean square) speeds of isotopes of Uranium

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Radioactive Decay of Dead Organisms

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