isotope help please!?

Question

I have a table and it looks like this

isotope # of protons # of electrons # of neutrons
Si-28
Si-29
Si-30

i dont know how to figure that out so if you can help me it would be great because I have looked all over the internet and I cant find an explinantion. Thanks!

That doesnt help, I need an example of how to find the electrons and neutons, I already know that there is 14 protons.

Answer 1

first you need to get out your periodic table of the elements

if you don't have one you can find it here:
http://periodic.lanl.gov/default.htm

then consider this definition from the wikipedia:
An isotope is any of several different forms of an element each having different atomic mass. Isotopes of an element have nuclei with the same number of protons (the same atomic number) but different numbers of neutrons. Therefore, isotopes have different mass numbers, which give the total number of nucleons—the number of protons plus neutrons. The term isotope comes from Greek and means "at the same place": all the different isotopes of an element are placed in the same location on the periodic table.

so, look on the periodic table and find that silicon (Si) has an atomic number of 14, so it has 14 protons, and 14 electrons (it always has to have 14 protons or it isn't silicon, it is something else on the periodic table (if it has 15 protons, its phosphorus)

remembering the widipedia definition that says isotopes have the same number of protons but a different number of neutrons we can figure that:

Si-28 has 14 protons, 14 neutrons
Si-29, 14 protons, 15 neutrons
Si-30, 14 protons, 16 neutorns

I left off the number of electons for each isomer so you could fill it in, which should be easy if you understoon any of this at all

the neutrons and protons together provide the atomic weight for the atom, which, according to the periodic table, for Si-28, (the even isomer) is 28.09

that periodic table is just full of fun, isn't it?

Answer 2

An isotope is any of several different forms of an element each having different atomic mass. Isotopes of an element have nuclei with the same number of protons (the same atomic number) but different numbers of neutrons. Therefore, isotopes have different mass numbers, which give the total number of nucleons—the number of protons plus neutrons. The term isotope comes from Greek and means "at the same place": all the different isotopes of an element are placed in the same location on the periodic table.

Answer 3

isotope # of protons # of electrons # of neutrons
Si-28 14 14 28-14=14
Si-29 14 14 29-14=15
Si-30 14 14 30-14=16

Answer 4

I'm not going to DO your homework, but this link should help:

http://www.webelements.com/webelements/elements/text/Si/isot.html

P.S. It's "explanation", not "explination", and all I did was a google search on "silicon isotope", so I think you didn't look real hard!