Nuclear chemistry Definition and 20 Threads

  1. H

    I Nuclear spin coupling in molecular (protium) hydrogen

    I'm not sure where this post belongs--here, or nuclear chemistry, quantum mechanics, NMR spectroscopy, etc. Moderator--please feel free to move it to a better location. I'm wondering if a container of liquid hydrogen subjected to a strong magnetic field would have both nuclei of each atom...
  2. HastiM

    Can C14 Atoms Be Detected Using NMR Despite 0% Natural Abundance?

    Homework Statement We want to image carbon C14 atoms using NMR with magnetic field of B=3 T. What frequency do we need to use? Use the following facts: C14 has 0% abundance, nuclear spin of I=3 and g=0.273 Homework Equations The frequency is given by f= (2⋅I) ⋅ (g ⋅B ⋅μ)/(1836 ⋅h), where μ...
  3. A

    Bombardment of Nitrogen-14 with an alpha particle

    Question: When alpha particles, having kinetic energy 3.0000 MeV bombard nitrogen-14 nuclei, oxygen-17 forms and the reaction releases a proton. Calculate the kinetic energy shared by the reaction products. Nitrogen-14 = 14.000307 amu Helium-4 = 4.00260 amu Oxygen-17 = 16.99913 amu Proton =...
  4. S

    Fukushima Is it safe to live 100 km from Fukushima for short time?

    I would like to know if is safe to stay in Sendai (less than 100 km from Fukushima). I have read different information in internet but I think is better to ask a expert, I am not sure about the radiation since it seems is not stable, it could be between 0.4-0.6 msv if I understood, is that ok to...
  5. N

    Shouldn't Carbon-14 concentration be the same everywhere?

    Why is it that newer organic matter has more carbon-14 than older organic matter? Isn't carbon constantly recycled, because of the carbon cycle? So C14-depleted carbon from old matter would enter the atmosphere, then be breathed in by new organic matter. The new matter would start off with...
  6. N

    Energy Change Nuclear Chemistry

    Homework Statement Determine the energy change, delta E, in J when 500 g of 229/90 Th undergoes the following nuclear reaction: 229/90 Th --> 225/88 Ra + 4/2 He The nuclear masses in amu or g/mol are: Th-229: 229.03175; Ra-225: 225.02360; He-4: 4.00260 Homework Equations delta E = deltam(c)^2...
  7. D

    A How to calculate the threshold energy of (n,n') reactions?

    Let us take the example of 89Y(n,n')89mY reaction. In the calculation of Q value we require mass of reactants and products. Both are same here. Then how to calculate the Q value of this reaction or how to calculate the threshold energy of this type of reactions?
  8. J

    Partial Half-Life of 22Na: Ec & β+ Emission

    Homework Statement What are the partial half of 22Na for decay by a)Ec b) β+ emission Homework Equations λ=ln2/T1/2 The Attempt at a Solution this what I do T1/2 =2.602 Yr λ=ln2/2.602 λ=0.266 yr-1what is the difference between a)Ec b) β+ emission there is no Percentage of each decay type.!
  9. J

    How to Calculate the Mass of 1μCi 241Am?

    Homework Statement what is the mass in g of the activity? (a)1μCi 241Am Homework Equations A = λN λ = ln2 / T1/2 The Attempt at a Solution A = λN 1μCi = λN N=1μCi/λ N = ( x /241 mol) × (6.022 × 1023 nuclei mol-1 ) 1μCi/λ=( x /241 mol) × (6.022 × 1023 nuclei mol-1 ) X=1μCi (241)/λ(6.022×...
  10. J

    What is the weight of a radioactive sample with a given half-life and activity?

    Homework Statement If a radioactive sample of 59Fe (t1/2= 44.496 d) has an activity of 1000 disintegrations per minute, what weight of 59Fe is present? Homework Equations
  11. patrickbotros

    Why doesn't an alpha particle have a +2 charge in alpha decay?

    The following equation is written in my book: 204Pb→4α + 200Hg If an alpha particle is a helium nucleus, why doesn't it have a +2 charge and why doesn't Hg have a -2 charge? Did my text just omit the charge?
  12. Q

    Nuclear Chemistry (determing masses from radioactive decay)

    I have been trying for quite some while but I can't seem to get this problem off the ground.1)Suppose that you hydrolyze 4.644 grams of a protein to form a mixture of different amino acids. To this is added a 2.80 mg sample of 14C-labeled threonine (one of the amino acids present).The activity...
  13. D

    Nuclear Chemistry - Solving U-238 Activity & Decay Energy

    Homework Statement Consider 238U which undergoes natural radioactive decay to form thorium-234 a)What is the activity, in curies, of 1.00 mg of U-238? B)What is the energy in kilojoules associated wuth the decay of 1.00 mg of 238U? The nuvlear mass of throium-235 is 234.0437 Homework...
  14. R

    Nuclear Chemistry: Kinetics of Radioactive Decay and Radioactive Dating

    Homework Statement A laboratory rat is exposed to an alpha-radiation source whose activity is 11.3 mCi. What is the activity of the radiation in disintegrations per second? in becquerels? The rat has a mass of 315 grams and is exposed to the radiation for 12.3 seconds, absorbing 39% of...
  15. B

    Nuclear chemistry reaction question

    Homework Statement Complete and balance the following nuclear equations by supplying the missing particle.^{98}_{42}Mo+^{2}_{1}H\rightarrow^{1}_{0}n+?Homework Equations The Attempt at a Solution I would think that the answer would just be ^{99}_{43}Te. It seems correct, since everything adds...
  16. S

    Nuclear Chemistry: Explaining Binding Energy and Mass Defect

    I'm doing a nuclear chemistry project right now, and I am able to solve all of the problems involving binding energy and mass defect, however I have one conceptual question. Why is it that when the nucleons combine with each other they let off energy? At first I thought it was their kinetic...
  17. L

    Is There a Difference Between Alpha Emission From and By Plutonium-242?

    Is there a difference between: alpha emission from Plutonium-242 to alpha emission by Plutonium-242?
  18. S

    Nuclear Chemistry: Solving Ionizing Intensity

    Homework Statement If X radiation ionizes 26.2 X 1012 atoms per cemtimeter cubed, what is the ionizing intensity of the radiation measured in roentgens ? Homework Equations The Attempt at a Solution Help, I have never seen atoms per centimeter cubed before, I know that 1...
  19. M

    Nuclear Chemistry: Iron Nucleus & Energy Needs

    Is it true an Iron nucleus requires the most amount of energy to hold it together? I would have thought it would be the larger the nucleus the more energy is required to hold it toghether.
  20. Q

    Why is mass not conserved in special relativity?

    Hi everyone, A couple days ago in chemistry we talked about nuclear chemistry. This of course is about halflifes, different types of decay, ect. I was surprised when I learned that an electron and a proton combine to create a neutron (electron capture). Now a couple days ago I was...
Back
Top