2016年6月27日 · Here's what I got. Strontium-90, ""^90"Sr", undergoes beta minus decay, so your goal here will be to use what you know about the emission of a beta particle to figure out the resulting nuclide. A beta particle, ""_(-1)^(color(white)(aa)0)beta, is simply a high-speed electron. When a radioactive nuclide undergoes beta minus decay, a neutron located inside its nucleus …

2015年10月20日 · "56 years" A radioactive isotope's nuclear half-life tells you how much time must pass until an initial sample is halved. In your case, strontium-90 is known to have a half-life of 28 years. THis means that if you start with an initial mass of strontium-90, let's say A_0, you will have A_0 * 1/2 -> after one half-life passes; A_0/2 * 1/2 = A_0/4 -> after two half-lives pass; …

2015年5月31日 · When uranium-235 undergoes a neutron-induced fission reaction, it will split into two smaller nuclei, which, in your case, are tellurium-137, ""^137"Te", and zirconium-97, ""^97"Zr", releasing neutrons and gamma rays in the process. So, you know that the uranium-235 nucleus must collide with a neutron, which is a subatomic paticle that has no electric charge and a …

The half-life of strontium-90 is 28 years. How long will it take a 44 mg sample to decay to a mass of 11 mg? Thorium-234 has a half-life of 24 days. if you started with 100 gram sample of thorium-234, how much would remain after 48 days?

2016年6月26日 · t_"1/2" = "29 years" The nuclear half-life of a radioactive nuclide, t_"1/2", is defined as the time needed for a sample of this nuclide to decay to half of its initial mass. The first thing to notice here is that it took 2.0 years for only "1 mg " - " 0.953 mg" = "0.047 mg" of strontium-90 to decay. This tells you that the half-life of the nuclide is significantly longer than …

2017年1月15日 · 0,25 g If the half-life of Sr-90 is 25 years it means that after 25 years its amount will be half the initial quantity. If you have 4,00 g, after 25 years you have 2,00 g; after 50 years you have 1,00 g; after 75 years you have 0,50 g; after 100 years you have 0,25 g

2014年7月16日 · The sums of the superscripts and of the subscripts must be the same on each side of the equation. Here are some links that show how to balance nuclear equations. http ...

2017年6月7日 · After four half lives 20.3125 is remaining and the sample is 115.2 years old. We start with 325 and divide by two this accounts for one out the four half lives. Which is 162.5 once again we divide by two and we get 81.25 this is two out of the four half lives. The third time we divide we get 40.625 and we do this one last time and arrive to the answer of 20.3125. So now …

2014年5月17日 · The amount remaining will be 6.2 g. The number of half-lives is n = t/t_½ For each half-life, you divide the total amount of the isotope by 2, so Amount remaining = "original amount"/2^n or A = A_0/2^n n = t/t_½ = (100" yr")/(25" yr") = 4.0 half-lives A = A_0/2^n = (100.0" g")/2^4.0 = (100.0" g")/16 = 6.2 g

2015年10月25日 · In this case, you are dealing with a strontium-90 isotope #""_38^90"Sr " -> # strontium-90 Read more about why stronyium-90 is considered a hazardous isotope here: