why do boron steel and cadmium rods absorb neutrons?

Answer 1

Certain isotopes, such as Boron-10, have what is called a high microscopic cross-section for neutron absorption. Almost all isotopes of all elements have a possibility of capturing a neutron that passes near it, but certain isotopes (that is, combinations of protons and neutrons in an atom's nucleus) are especially good at capturing neutrons. It's like the difference between me playing wide receiver and a professional wide receiver. If the ball is thrown right at me at just the right speed in just the right way, I might actually catch the ball, but if the quarterback's throw is just slightly off, I'm not going to catch it. However, the pro is able to run around the field and can jump or dive as necessary to catch the football. Same way with boron-10 as compared to other isotopes. A neutron doesn't need to make as direct a hit on B-10's nucleus for B-10 to capture the neutron. The units for cross-sect of absorption are barns (kind of like talking about hitting the broad side of a barn with one's throw). As for why some isotopes have biger cross-sections of absorption, it's just because some nucleus arrangements are more welcoming to neutrons. Neutrons, being uncharged, often pass through an atom, possibly even very near the nucleus, without interacting. Some isotopes' nuclei though do a better job of sucking up neutrons that pass nearby.

It's important in the nuclear industry to have neutron absorbers. To control a reactor's power at a constant level, the amount of neutrons that produce fission in one second has to equal the amount of neutrons that will produce fission in the next second. However, every fission (which is caused by only one neutron) produces over two neutrons. To keep power stable, over half of the neutrons produced can't be allowed to themselves cause fission. Most of the neutrons that won't causes fission will escape from the reactor, but to fine tune the amount of neutrons that cause fission, neutron absorbers (i.e., control rods) are pulled in and out slight amounts to increase or decrease the amount of neutrons that are absorbed so that they won't cause fission a little bit later.

Answer 2

Neutron Absorbers

Answer 3

This Site Might Help You.

RE:
why do boron steel and cadmium rods absorb neutrons?

Answer 4

A control rod is a rod made of chemical elements capable of absorbing many neutrons without fissioning themselves. They are used in nuclear reactors to control the rate of fission of uranium and plutonium.

The absorption neutron cross section of an isotope of a chemical element is the effective cross sectional area that an atom of that isotope presents to absorption.

Chemical elements with a sufficiently high capture cross section for neutrons include silver, indium and CADMIUM. Other elements that can be used include BORON, cobalt, hafnium, gadolinium, and europium. Because these elements have different capture cross sections for neutrons of varying energies the compositions of the control rods must be designed for the neutron spectrum of the reactor it is supposed to control

Answer 5

what is this 20 questions? there literaly are 20 questions this is too much to post your cheating i know some of these but im not going to help you cheat what did you post the entirety of your homework