Radioactive Definition and 391 Threads

might be more expensive than uranium or plutonium, but storage costs and environmental impact and anti-nuke activism might be muted if there was an isotope of any element, say an isotope of iodine, that when fissioned, gives off energy AND short-lived radioactive isotopes. so, say...

During radioactive decay, what determines if the emission of a beta particle will be positronic or electronic?

In my assay of 50uL of 125-I-insulin I have 20,000 cpm at the expiry date. The half life of 125-I-Insulin is 60 days. So how can I calculate how many counts a 50uL sample of 125-I-labelled insulin would contained at 4 months past the expiry date? cheers

I need a refresher on calculus need to derive this equation, the question is: A --> B --> C and where decay constants: http://img183.imageshack.us/img183/4403/aki2.jpg Derive an expression for the activity of B as a function of time. So what I'm having trouble with is changing the...

Staight question : Can a radioactive element decay by emmitting more than 1 particles at once? ie. can a radioactive Uranium decay 2 beta and 1 alpha particles at the same time, or it must decay 1 particle (eg beta), itself becomes another elements and then decay further? thanks

The Range Of Half-lives Of Different Radioactive Elements Is From_______ A)hours To Years B)hours To Weeks C)days To Months D)seconds To Billions Of Years E)days To Weeks

Hi, Is it possible to induce decay in a radioactive element by introducing vast amounts of high-energy electrons in the hope that they would be absorbed via electron capture? I was thinking about how to use up all the reactor waste that the US generates (I live in Washington State, a great...

I've searched for a simple definition, but i couldn't find an illustrated clear one. It's about the study of tautomerism using radioactive isotopes, or tracers.

Hey, I have been set this question, and I am finding it extremely difficult to begin. So much information is given, I don't know how to start to answer it. Also, some of the terms are confusing... A living specimen in equilibrium with the atmosphere contains one atom of 14C (half-life =...

Would i be right in saying that if a radioactive material (e.g. Uranium) is placed into sealed box then it would not radiate? i came to this conclusion through the Heisenburg uncertainty principle. If the particles making up the uranium are not measured then they don't decide on a quantum state...

Natural Uranium found in the Earth's crust contains the isotopes A=235 and A=238 in the atom ratio of 7.3*10^-3 to 1. Assuming that the time of formation of the Earth these two isotopes were formed equally, and that the mean lives are 1.03*10^9 years and 6.49*10^9 years respectively, show that...

I was wondering, and it baffles me, how is the strong force involved in radioactive decay? I know ecxatly how the weak force is involved but that's about it. Thanks

Hi, I was doing this question & I just want to make sure I've got it correct: A quantity of DNA was labelled with radioactive nitrogen. It was then allowed to replicate three times using non radioactive to synthesise the new DNA strands. What proportion of the final mass of DNA would you...

Okay, I've got this problem in my Chemistry class. It's about half-lifes and all that. If this is the wrong place to post this, then somebody can move it I guess. I've got a 10.0 g sample of an unknown. They give me the following info, wanting me to plot it on a graph. That's the easy...

Is it possible to identify such an isotope? What are my choices if I wanted such a long half-life product. (Ultimately, I need it to activate a timing switch...!) :smile: Thanks, anyone for any pointers. AA

The carbon in living matter contains a fixed proportion of the radioactive isotope carbon-14. The carbon-14 in 1.00g of carbon from living matter has an activity of 0.250Bq. The half-life of carbon-14 is 5730. When a plant dies the proportion of carbon-14 decreases due to radioactive decay. A...

Q: A 50-g chunk of charcoal is found in the buried remains of an ancient city destroyed by invaders. The carbon-14 activity of the sample is 200 decays/min. Roughly when was the city destroyed? A: I used R = Ro*e^(-lambda*t) and t1/2 = ln2/lambda t1/2 = 3.834*10^-12 s-1 and 200...

Just wondering, why are some atoms radioactive and others not?

Simple question, but i don't know where to start. The half life of one radioactive isotope of sodium is 2.6 years. Show that its decay constant is 8.4 x 10^-9 s^-1. Thanks in advance, Ben.

A magnet is directly between a Geiger counter and a radioactive material. If no radioactivity is registered, what kind of particles are being emitted by the radioactive substance?

is there exists radioactive compound, such as uranium compound with some other elements? does the bonding of atoms into molecules make radioactive decay more difficult? causing "screening" effect for example? thanks.

I have my doubt , solution and the question in the attachment that followed. Thanks for anybody that spend some time on this question.

When finding the quantity of a radioactive substance remaining after a half life of time t, using the formula, T1/2=.693/lambda. do u have to convert the time to standard units, the second, if it is in mins, or yrs or days or months watever?

I have my doubt,solution and question in the attachment that followed.Thanks for anybody that spend some time on this question.

Does time dilation effect radioactive decay rates? A quick search on google seems to say no. This would imply that if the twins paradox was executed, that when the traveling twin returned home, after say 2000 Earth years have passed, we would carbon date him at 2000+ years old. What would...

A 2.71g sample of KCL is found to be radioactive, and it is decaying at a constant rate of 4490 Bq. The decays are traced to the ekement potassium and in particular to the isotope K(proton number 40), which constitutes 1.17% of normal potassium. find the half-life of this nuclide( Take molar...

My uncle was in WWII, and after we bombed japan , he was send over there for some duty. When he came home he brought some belongings from japan, like his uniform, Gun,, ETC...He passed away this year and left some of his WWII things to me that he brought back from japan. My question is, IF these...

What properties do radioactive substances have that actually cause harm to organisms? I've really no idea at all... Thanks alot, Jacob

Possibly a topic of conversation here... Has anyone heard of this book / story? It really is amazing-scary. Possibly the most strange aspect about it, for me, is that it happened in my subdivision. I talked to a few neighbors who were there when things came to a head. The original...

Im trying to get over OCD, maybe someone can help me with some irational fears. I hate to change batteries in my smoke dector because a stray chunk of radioactive material might have come loose. #2 Ill never wear a watch with tritium on the hands because, well it just freaks me out. #3 I drive...

an alpha particle from a certain radioactive source has a Kinetic energy of 8.2x10(-13)j. Using the information below, estimate how long it would ctake this particle to travel a distance equal to the diameter of the atom. mass of alpha particle= 6.6x10-27kg diameter of atom=1x10-10m my...

As the temperature increases and pressure remaining constant. Does the half-life of a radioactive element stay the same? Also, Which gaseous radioactive waste product that is released into the atmosphere after it has decayed to a safe radiation level? radon-222, radium-226, cesium-137...

hi I'm new here hope you can help me with this problem nuclei A decays to B and then to C(stable) A and B have the same decay constant, n Initially the amount of A is N(0)>0 while B and C are zero then the amount of A at any time is : N(t)=N(0)exp(-nt) can somebody derive the equation for...

Is there any way to recycle nuclear waste or to stop its radioactivity/emissions besides burying it like a dog? Re: http://www.russiajournal.com/news/cnews-article.shtml?nd=41147

I was viewing a site on the flat Earth society when I came across their application form to join. Here are a few ridiculous things listed: Favorite Radioactive Isotope: Favorite Mineral: Favorite Eastern European Nation: Favorite Presidential Cabinet Member Which is your...

5. Radioactive and heavy isotopes can be used to label biochemical molecules. Describe how their use has enabled scientists to understand biochemical pathways and processes. Can anyone direct me to any decent websites that might give some info related to this? Thanks for your help.

Question #1: Can I speak of an atom decaying because one or more of its particles exceeded "escape velocity" according to statistically observed decay rates and a unit of the particle's former affiliation fell apart post-escape somewhat, and the atom was changed into an isotope or some other...

How long does radiactive material remain radioactive.? I ask this in light of the issue of Earth's core heating. It seems to me the radioactivity model has to explain how such material remains seemingly radioactive to this day. 4.5 billion years after the Earth was formed. Does that...

What properties of nuclei make them radioactive? I know it is mainly to do with stability of the nucleus, but are there any other reasons? Why are elements with smaller nuclei less radioactive than elements with larger nuclei?

If you take two identical radioactive samples, place one on Earth and another on a near-lightspeed spaceship, and compare them some time later, will the one left on Earth have undergone comparatively more radioactive decay than the one on the spaceship? If the experiment is repeated by...

I was wondering if I could get some guidance regarding the following question: "A radioactive nucleus, moving in a straight line, decays and emits an alpha particle. In the rest frame of the nucleus, the emitted particle moves with a velocity 6c/7, at an angle of 60 degrees to the direction...