How do you find how many protons, neutrons, and electrons are in an element using the element table?

Question

I have a quiz today, apparently...

If you can explain this so I can easily understand, thank you!! :D

Answer 1

To find the number of nuetrons you take the atomic mass and subtract the atomic number.

The atomic number is always equal to the number of electrons and also the protrons unless

If it has a negitve charge it has an extra electron, positive charge it is missing one. These are called positve and negative ions.

Some atom masses vary on the chart, that is because the molecule has a different amount of nuetrons, these variations are called Isotopes.

Get it?

Answer 2

The number of protons is the easiest. The Atomic Number IS the number of protons. Since there are equal numbers of protons and electrons in atoms, the Atomic Number is also the number of electrons.

For neutrons, it gets tricky. The number of neutrons should be approximately the Atomic Mass - number of protons. Unfortunately some elements come in different forms, called istopes, each with a different number of neutrons. Hydrogen, for example, comes in protium (normal no-neutron hydrogen), deuterium with two neutrons, and tritium with three. Still 1.01 - 1 = 0.01 ~ 0, which gives you the most common amount (0). But on some elements, like chlorine, there is a large amount of two isotopes, and you will get a fractional number of neutrons.

Answer 3

the atomic number is equal to the number of protons in an element. Protons and electrons are also the same so use the same number. For neutrons take the atomic mass and subtract the number of protons. Its easy!

Answer 4

The atomic number gives the number of protons in the nucleas. Because an atom is electrically neutral, the number of protons equals the number of electrons.

The atomic weight is the number of protons plus the number of neutrons so subtracting the atomic number give the number of neutrons (after you round off the decimal places).

Answer 5

The atomic number gives the number of protons in the nucleas. Because an atom is electrically neutral, the number of protons equals the number of electrons.

The atomic weight is the number of protons plus the number of neutrons so subtracting the atomic number give the number of neutrons (after you round off the decimal places).