Atoms

Today you are going to learn how to determine things like isotopes, number of protons, number of neutrons, etc. So lets get started!


REVIEW: Atoms consist of electrons, protons and neutrons.




Proton: Mass = 1, charge = +1, located in the nucleus

Neutron: Mass >1, charge = 0, located in the nucleus

Electron: Charge = -1, located around the nucleus




Atomic Number: Number of protons found in a nucleus


The atomic number = the number of protons which also equals the number of electrons. It's that easy!


Got all that? Time to move on to ions.

Ions are atoms able to gain or lose electrons
The number of protons subtracted by the number of electrons equal the charge of the ion.

Moving on to the mass number. This is the total number of protons and neutrons!
Knowing this, here are some equations to remember:

number of neutrons = mass number - atomic number

mass number = number of protons + number of neutrons

Moving on to atomic mass!

Atomic Mass: the average mass of an isotope

Wondering what an isotope is?

Isotopes: when there is the same number of protons and electrons but a different number of neutrons

Here is a problem that deals with isotopes:

There is an element with 4 naturally occuring isotopes. Their atomic mass and percent is as follows: a = 46 (25%), b = 47 (50%), c = 48 (15%), and d = 49 (10%)

Find the atomic mass for the element.
First, multiply the atomic mass by the percent abundance.

A = 36 x 25 = 11.5
B = 47 x 50% = 23.5

C = 48 x 15% = 7.2

D = 49 x 10% = 4.9

Now add them together to get your answer.

11.5 + 23.5 + 7.2 + 4.9 = 47.1

I just high-fived my cat who is sitting beside me so I felt this picture was necessary.

Thanks for reading!