Atoms

Atoms

1. Number of protons = Number of electrons (Charges are the same size)

   • Atoms are neutral therefore they have an overall charge of 0.

2. Charges of atoms: Protons-+1, Neutrons-0 and Electrons have a charge of -1.

   • Atomic number tells you how many protons there are.
     • Number of neutrons=mass number - atomic number
       • Mass number tells you the total number of protons and neutrons
       • Maximum capacity of the first three shells energy level or shell: maximum number of electrons first-2 second-8 third- 8

3. There are electrons surrounding the nucleus in energy levels/shells.

   • An atom is the smallest constituent unit of ordinary matter that has the properties of a chemical element.
   • Different energy levels can hold different numbers of electrons.

4. Atoms are made from smaller subatomic particles.