Atom

Atom

1. Protons

   • Have a positive charge
     • In charge calculations, they have a charge of +1
   • Have a mass of 1
   • The number of protons determines its element and basic properties

2. Neutrons

   • Have no charge
     • Don't use them when calculating charge
   • Have a mass of 1
     • Same mass as proton
   • They are essential to holding the atom's nucleus together
     • Because like charges repel, neutrons have to 'hook' onto the protons and keep them from flying apart
       • They are like the glue in the nucleus

3. Electrons

   • Have a negative charge
     • In charge calculations, they have a charge of -1.
   • They are found in electron clouds around the nucleus
     • They orbit in different shells or orbitals
       • The farther the electron is from the nucleus (the bigger the orbital is ), the more energy the electron is said to have
         • This amount of energy is a whole number called the Principal Quantum Number
       • Electron configuration is a type of notation used to describe how electrons are arranged in an atom
         • A number means the principal quantum number
         • A letter means the type or shape of the orbital
         • An exponent is the number of electrons in that shell
   • They have a mass that is 1836x less than protons or neutrons
     • In mass calculations, they are considered to have 0 mass

4. Atoms are electrically neutral when they have the same number of protons and neutrons

   • When atoms aren't electrically neutral, they are called ion.
     • If an atom's charge is positive, it is called a cation.
     • If an atom's charge is negative, it is called an anion.

5. Atomic mass is, simply, the number of protons + neutrons.

   • Relative Atomic Mass is a weighted average of all of the isotopes of an element,
   • Isotopes are essentially different versions of the same element, with the same number of protons, but a different atomic mass
     • Isotopes only have a different atomic mass

6. Molecule: 2 or more atoms bonded together

7. Quarks: small subatomic particles that make up protons and neutrons

8. Atomic Model through History:

   • 1. Greeks thought of a few basic elements and even thought of the idea of atoms
     • 2. Ernest Rutherford: Proposed the nuclear model of the atom, with a dense, positively charged core and small, negatively charged electrons orbiting around them.
       • 3. Niels Bohr: A student of ER who further advanced the study of electrons and deepening our understanding of atomicbehavior.