Answer:
Hi, this is a super vague question, so its pretty confusing to answer. Could you please be a bit more specific?
If you are referring to chemistry, then how you tell "what is what" is by the molecular makeup of an element (Periodic table), and "how that..affects what", chemical reactions can occur between elements
If an least one neutron from U-235 fission<span> strikes another nucleus and causes it to fission, then the chain reaction will continue. If the reaction will sustain itself, it is said to be "critical", and the mass of U-235 required to produced the critical condition is said to be a "</span>critical mass<span>". A critical chain reaction can be achieved at low concentrations of U-235 if the neutrons from fission are </span>moderated to lower their speed, since the probability for fission with slow neutrons is greater. <span>A fission chain reaction produces intermediate mass </span>fragments<span> which are highly </span>radioactive<span> and produce further energy by their radioactive decay. Some of them produce neutrons, called </span>delayed neutrons<span>, which contribute to the fission chain reaction.
Hope this helps you..</span>
Answer:
The rate is a mathematical relationship obtained by comparing reaction rate with reactant concentrations.
The answer is (1) 90 Sr. The definition of beta decay is that a type of radioactive decay in which one proton will change to one neutron and release one electron inside the nucleus. And 90Sr is a common beta emitter.
To change only one variable which is very important than to test the experiment to match the hypothesis again, I think. It’s been a while since I was on that lesson♀️