Activity 1: Atoms and Molecules

Activity 1: Atoms and Molecules

1. ATOM STRUCTURE

   • NEUTRON: is a subatomic particle found in the nucleus of every atom.
   • ATOM: is the smallest component of an element that retains all of the chemical properties of the element
     • MOLECULE: A molecule refers to two or more atoms which have chemically combined to form a single species.
     • ION: An ion is an atom or group of atoms in which the number of electrons is different from the number of protons
       • If the number of electrons is less than the number of protons, the particle is a cation (+). If the number of electrons is greater than the number of protons, the particle is an anion (-).
   • ELECTRON: Is a negatively charged subatomic particle.
   • PROTON: has a positive charge.
     • ATOMIC NUMBER: The number of protons in an atom
       • ELEMENT: Determined by the atomic number. Cannot be broken down into tinny components
   • ISOTOPES: Have the same number of protons in the nucleus or same atomic number, but have different numbers of neutrons in the nucleus, or different atomic weights
   • ATOMIC MASS: Indicates the size of an atom. Average mass of atoms

2. OCTET RULE

   • Elements strive to become a noble gas and have a stable configuration
   • States that atoms of low atomic number tend to combine or become ions so that they each have eight electrons in their valence shell.

3. MOLECULAR ORBITALS

   • Mathematical function that describes the behavior of an electron in a molecule
   • Can be expressed in 3 different ways
     • Antibonding
     • Nonbonding
     • Bonding

4. ELECTRONIC CONFIGURATION

   • DEFINITION: The distribution of electrons among the orbital shell
   • ORGANIZATION: The s orbital- a single orbital (2 electrons). The p orbital- 3 orbitals (6 electrons). The d orbital- 5 orbitals (10 electrons). The f orbital-7 orbitals(14 electrons)
     • 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p, 8s.

5. QUANTUM NUMBERS

   • DEFINITION: Is a value that is used when describing the energy levels available to atoms and molecules
   • FOUR QUANTUM NUMBERS
     • n - principal quantum number - energy level
     • ℓ - angular momentum quantum number - subshell
     • m - magnetic quantum number - orbital of the subshell
     • s - spin quantum number - spin

6. ATOMIC MODEL

   • 1. DALTON'S MODEL: Solid sphere
   • 2. VORTEX'S MODEL: Model in which atoms are twisted knots
   • 3. THOMNSON´S MODEL: Discovered the electrons
   • 4. RUTHERFORD´S MODEL: Nuclear model
   • 5. BOHR´S MODEL: Planetary model --> orbits
   • 6. SCHRÖDINGER´S MODEL: Electron cloud model
   • 7. ACTUAL MODEL