How do scientist calculate the number of electron, neutron, and proton in an atom?

Answer 1

One way is by measuring the energy of certain electrons that are ejected from an atom. When you hit an atom with a certain amount of energy, usually in the form of a photon, it can give up this energy to an electron. When an electron from a specific shell of an atom acquires enough energy is to be ejected it leaves a hole that one of the other electrons wants to fill. This electron is from a higher energy level so it has to give off energy to go down to this lower orbit. This energy is also in the form of a photon. By measuring the energy of this photon, you can calculate the number of protons in the nucleus. This tells you what atom it is.

I am sure there are other ones, but the one that I am familiar with is called a Kappa-alpha x-ray. This is observed when an electron from the n=1 level, or S shell, acquires enough energy to be ejected and then an electron from the n=2 level gives off the x-ray in its transition to the lower level.

Knowing the number of protons tells you the number of electrons is has. Well, at least how many it had before you got rid of one.

As far as neutrons, you can do some measurements of its vibrational or rotational energy. These measurements are quantized, which means they only take on specific values. You can then do some more calculations to find our what the total nuclear mass is. Knowing the number of protons you can find out the number of neutrons.

I'm sure there are much more sophisticated ways of determining this, but there are the ways that I know work... if you can make the measurements.

Answer 2

1897 Thomson discovers the electron 1911 Rutherford discovers the nucleus 1932 Chadwick discovers the neutron etc etc. someplace between Thomson and Chadwick, physicists found out that there are surely charged components of the nucleus, which we call 'protons'. the way this occurred became a steady technique, and due to this it is not ordinary to assert precisely who got here upon the proton, besides the very incontrovertible fact that in case you had placed a recognition against it, it may be Ruthford, style of. After the invention of the electron, it became found out that there must be beneficial cost centers in the atom to stability the adverse electrons and create electrically independent atoms. Rutherford's discovery of the nucleus validated that those beneficial expenditures have been concentrated in an quite small fraction of the atoms' volume. In 1919 Rutherford got here upon that he ought to alter one ingredient into yet another by making use of surprising it with energetic alpha debris (which we now understand are in simple terms helium nuclei). in the early 1920's Rutherford and different physicists made a type experiments, transmuting one atom into yet another. In each and every case, hydrogen nuclei have been emitted in the approach. It became obvious that the hydrogen nucleus performed a elementary place in atomic shape, and by making use of comparing nuclear lots to expenditures, it became found out that the beneficial cost of any nucleus must be accounted for by making use of an integer form of hydrogen nuclei. by making use of the overdue 1920's physicists have been in many situations bearing on hydrogen nuclei as 'protons'. The term proton itself seems to have been coined by making use of Rutherford, and known looks in print in 1920.

Answer 3

For any atom the mass number and the atomic number would be mentioned or one would have to look up the periodic table for this data. Then use the following formulas::

1.number of electrons = number of protons
2.number of neutrons = mass number - number of protons
3.atomic number = number of protons

Answer 4

John Dalton, spectronomy and molecular mass measures and laws of proportions.
http://en.wikipedia.org/wiki/John_Dalton
http://en.wikipedia.org/wiki/Atomic_mass_unit
http://en.wikipedia.org/wiki/Spectrometer
http://en.wikipedia.org/wiki/Molecular_mass

Answer 5

Hmmmmm...Now why would you want to know about all that calculating...Thinking of making a "Superbomb" or something!? =<)