Introduction to Chemistry: Test 2

Chapter 4:

• Atomic Theory: All matter is composed of atoms, which are composed of protons, electrons, and neutrons.

  Models of the atom:

  • Democritus: “Atomos”.
    - There must be some smallest, fundamental, particle of matter.

    - No experiments —> Philosophy of the atom.

  • Dalton: “Atom”.

    - Tiny, hard, unbreakable sphere.

    - Did experiments.

  • J.J. Thompson: “Electron” “Cathode ray tube”.

    - Atoms are breakable.

    - Choc chip cookie dough model:

    • Tiny negative electrons in mass and positive charge.

  • Rutherford: “Nucleus”.

    - All positive charge and most of mass was concentrated in a tiny, positive nucleus.

    - Most of an atom is empty space.

    - Mass + Charge in tiny nucleus.

  • Bohr: “Orbit”.

    - Electrons orbit the nucleus like planets in a solar system.

  • Quantum Mechanical model: “Wave”

    - Electrons orbit the atom in random ways.

    - Surrounded by an electron cloud containing all the possible places that the electron might be.

  • Electron is treated mathematically as a wave.

  Table of subatomic particles:

  Subatomic Particle	Symbol	Location	Charge	Size
  Electron	e-	Outside nucleus	-1	1/2000 amu
  Proton	p+	Inside nucleus	+1	1 amu
  Neutron	no	Inside nucleus	0	1 amu

• Atomic number: # of protons in the nucleus.

• Mass number: # of protons + neutrons.

• Isotope: Same element, different number of neutrons.

• Atomic mass: Weighted average mass of all known isotopes of an element.

Light Spectrum:

• Light is a wave.

• Wavelength: Distance light travels n one cycle.

• Frequency: # of wave cycles completed in each second.

• Light travels at a constant speed.

  

Notation

• Spectroscopic Notation:

  • 1S, 2S, 2P, 3S, 3P, 4S, 3D, 4P, 5S, 4D.

  • Letter meanings:

    • S fits 2.

    • P fits 6.

    • D fits 10.

  • Ex: Phosphorus

    • 1S², 2S², 2P^6, 3S², 3P³.

• Noble gas shorthand: Same thing but start with noble gas from one row above.

  • Ex: Cobalt

    • [Ar] 4S², 3D^7.

Chapter 5:

Periodic Table:

• - Metalloids: Boron, germanium, silicon, antimony, arsenic, tellurium and polonium.

  Periodic trends:

• Charges:

  • 1A: +1

  • 2A: +2

  • 5A: -3 (nonmetals)

  • 6A: -2

  • 7A: -1

Chapter 6:

Nomenclature:

• Binary Ions:

  • Metal + Nonmetal

    • Metals keep their name

    • Nonmetals retain their root name followed by -ide.

  • Examples:

    • Potassium Oxide = K2O

    • Aluminum Iodide AlI3

• Binary Molecular:

  • Two and only TWO NONMETALS.

    • Name first element’s full name.

    • Name second element -ide.

    • Use prefixes to show suffix.

      Mono: 1, Di: 2, Tri: 3, Tetra: 4, Penta: 5, Hexa: 6, Hepta: 7, Octa: 8

  • Examples:

    • Nitric Oxide = NO

    • S2Cl2 = Disulfur dichloride

• Binary Acids:

  • Acid made up of hydrogen combined with another atom.

    • Hydro- + root name of the other element + -ic acid.

  • Examples:

    • H2SO4 = Sulfuric Acid

    • HNO2 = Nitrous Acid

    • H3PO4 = Phosphoric Acid.