Explore BrainMass

Explore BrainMass


    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.

    © BrainMass Inc. brainmass.com May 25, 2024, 10:48 am ad1c9bdddf

    BrainMass Solutions Available for Instant Download

    Atomic Arrangements of Permanent Magnets

    1. Name the three kinds of strength used to characterize materials AND give an example of a material that are strong in each of these modes. 2. Explain how atoms can be arranged in such a way to create a permanent magnet. 3. Identify 10 objects in your home that use semiconductors. What other kinds of materials with special el

    Energy: Laser Fusion

    Please provide a short paragraph on fusion progress. Please read over the Nature paper (perspective) on laser fusion and present your thoughts with regard to the viability of this approach and if it is better or worse than solar, wind, biomass. "Laser fusion on the horizon" NATURE PHOTONICS | VOL 6 | MAY 2012 | www.natu

    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

    1. Compare the nuclear radii of the following nuclides: (2 1H), (60 27Co), (197 79Au), (129 94Pu). 2. Calculate the average binding energy per nucleon of (a)(23 11Na) Sodium, (b) (60 27Co) cobalt, and (c) (107 47Ag) Silver 3. The peak of the stability curve occurs at 56Fe, which is why iron is prominent in the spectrum of

    Calculating binding energy using Excel

    Calculating binding energy using Excel. See attached file for full problem description. Use the SEMF and the coefficients given in the caption to calculate the total binding energies of Ni, Co, Fe, and Mn. Which terms are different in the four cases? Why are they different?

    Chernobyl products half life analysis

    See attached file for full problem description. Among the radioactive products emitted in the 1986 Chernobyl reactor accident were 131I (t1/2 = 8 days) and 137Cs(t1/2 = 30 years). There are about five times as many 137Cs atoms produced in fission. a) Which isotope contributes the greater activity to the radiation cloud? A

    Strontium 90 is a radioactive isotope produced in hydrogen bomb explosions.

    Strontium 90 is a radioactive isotope produced in hydrogen bomb explosions. The aboveground nuclear test ban treaty of 1963 was based on evidence of Sr-90 contamination of milk and human bones. The half-life of Sr-90 is 29 years. Suppose no new sources of Sr-90 have contaminated the atmosphere since 1963. Determine what frac

    Energy Released by Fusion

    A simplified model of fusion reaction would have two deuterium atoms (an isotope of hydrogen with 1 proton and 1 neutron in the nucleus) combine to form an atom of helium. If the mass of each deuterium nucleus is 3.3444 x 10^-27 kg and the mass of the helium nucleus is 6.6465 x 10^-27 kg, how much energy is released when 1 kg o

    Nuclear Physics Calculations

    A patient undergoing radiation therapy for cancer receives a 215-rad dose of radiation. (a) Assuming that the cancerous growth has a mass of 0.17kg, calculate how much energy it absorbs. (b) Assuming the growth to have the specific heat of water, determine its increase in temperature. Answer A. 0.37 J B 0.51 mK A d

    Radioactivity; Activity and Half-life

    3. The half-life of iodine-131, an isotope used in the treatment of thyroid disorders, is 8.04 d. (a) If a sample of iodine-131 contains 5.0 1016 nuclei, what is the activity of the sample? Express your answer in curies. (b) If the half-life of iodine-131 were only one-fifth of its actual value, calculate the factor by wh

    Activity of naturally occurring potassium

    The naturally occurring isotopes of Potassium are: 39K (abundance 93.10%) 40K (abundance 0.0118%) 41k (abundance 6.88%) 40 K is radioactive and decays by B-decay with a half life of 1.29 multiplied by 10^9 years. Question: Using the definitions for the decay constant and for the Becquerel, calculate the activity of 1

    Atomic Physics Question

    Question: The naturally occurring isotopes of potassium are: 39 K (abundance 93.10%) 40 k (abundance 0.0118%) 41 k (abundance 6.88%) 40K is radioactive and decays by Beta- decay with a half-life of 1.29 multiplied by 10`9 years. a) How many protons and neutrons does each of the three isotopes of potassium have? b)

    Isotope half-life

    I am looking for the solution for this problem. Please show all assumptions, set up, and a detailed solution. I need set up, solving the equation and the final amount of material at any time. A certain isotope has a half-life of 5 years. A sample of the isotope has... Please see attached.

    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

    1. A 500-microFarad capacitor is discharged through a 4.7-Mega ohm resistance. What is the time constant? a. 600 s b. 300 s c. 2350 s d. 1200 s 2. Water in a fish tank is 7.6 feet deep, and a coin rests on the bottom. How far below the surface does the coin appear to be when viewed from above? (Assume a

    rms (root mean square) speeds of isotopes of Uranium

    Uranium has two naturally occuring isotopes. 238U has a natural abunchance of 99.3% and 235U has an abundance of 0.7%. It is the rarer 235U that is needed for nuclear reactors. The isotopes are separated by forming uranium hexafluoride UF_6, which is a gas, then allowing it to diffuse through a series of porous membranes. 235UF_

    Radioactive Decay of Dead Organisms

    Radioactive Decay Carbon-14 is a radioactive Isotope of Carbon-12. How many protons and neutrons are in the nucleus of C-12? __________ In C-14 ___________ While an organism is alive, the ratio of Carbon-14 to Carbon-12 is in equilibrium. This does not mean that there are equal amounts of C-14 and C-12, but rather, their pr

    Properties of nuclei

    Singly ionized carbon is accelerated through 1000 V and passed into a mass spectrometer to determine the isotopes present. The magnetic field strength in the spectrometer is 0.200 T. (a) determine the orbit radii for the 12C and 13C isotopes as they pass through the field. (b) Show that the ratio of radii may be written in the

    Half life of the isotope

    A radioactive isotope of mass number 94 has been prepared by neutron bombardment. If 4.7 ug (1 ug = x 10 ^-6 g) of this isotope registers 20 counts per minute on a radioactivity counter, what is the half life of this isotope?

    Magnetic force in conductors; nuclide of a transuranium element

    PART ONE: The magnetic force between two long, straight, parallel conductors: A) increases as the distance between the wires decreases B) decreases as the length of the wires increases C) increases as the current in either wire decreases D) is independent of the length of the wires PART TWO: A nuclide of a tra