How do I know how many neutrons are in an elements atom?

Question

Gold atom=how many neutrons

Answer 1

i agree with everyone, it is 118.
but here are some websites that might help you.

http://misterguch.brinkster.net/subatomic%20particles.html
http://www.wikihow.com/Find-the-Number-of-Neutrons-in-an-Atom

Answer 2

Actually, for most elements, there is no single answer to the question. The atomic weight is a weighted average of the atomic weights of all isotopes of that atom. Generally, one isotope is the most common, and subtracting the atomic number from the atomic mass will tell you how many neutrons are in that isotope. But there may be other isotopes with different numbers of neutrons. You can find out how much of an element is made of each isotope, and how many neutrons each one contains, in Wikipedia.

In the case of gold, there is only one naturally-occuring isotope, which is stable and contains 118 neutrons. There are also a whole bunch of synthetic isotopes, all of them radioactive, with between 90 and 126 neutrons.

Answer 3

118 subtract the atomic number (79) from the mass number (197)

also elements over twenty have an approximate proton to neutron ratio of 2:3 so if gold has 79 protons it must have 118

Answer 4

to find out the number of nuetrons in an atom, take the atomic mass (rounded to the nearest integer) and subtract the atomic number (which is the number of protons) this is because most of the mass of an atom is in the nucleus.

the # of neutrons in gold: 197-79=118

Answer 5

It varies www.gold.org for detailed info