Recap on Atom Structures

J. Dalton defied the atom.

We only have models of the atoms, no one’s “really sure”.

Atoms have equal amounts of electrons and neutrons, otherwise they’re Isotopes.

Necessary knowledge:

· Netrons have a mass of 1.

· Protons have a mass of 1. And are positively charged.

· Electrons have a mass of 0.00055. And are negatively charged.

Despite that electrons are what’s more involved in chemical reactions, chemists are also interested in the nucleus, where protons and neutrons are, because they define and guide what the element of the atom is, or if it’s an isotope.

Isotopes have different amount of neutrons, so they have the same charge as their father element. So, not to be confused with ions.

Some Isotopes are referred to as Radio Isotopes, because we use them in Radiology examinations, as they can be digested and tracked around the body. Examples include ⁴⁸Calcium & ⁹⁰Strontium.

- Periodic table guide!

Protons and electrons are the small number.

Neutrons is the big number, take away the small one. If not equal to small number, then it’s an isotope.

We can find the RAM of an atom via knowing the quantities of it's isotopes in a specific setting, we then multiply each isotope's number with its percentage quantity, add them up, and divide by a hundred. For example:

Q. What is the relative atomic mass of Chlorine, if it contained 75% Cl³⁵ and 25% Cl³⁷?

((75 x 35) + (25 x 37)) / 100 = 35.5