Chemistry

• Periodic Table

  Organizes all the elements based on their masses
• Periodic Table

  • Provides information about all the elements
  • Organized by types of elements and chemical families
• Types of elements on the Periodic Table

  • Metals
  • Non-Metals
  • Metalloids
• Metals

  • Found on the left side of the periodic table
  • Shiny appearance
  • Solids at room temperature, except for Mercury (a liquid)
  • Soft, malleable, ductile, and bendable
  • React with acids, conduct heat, and electricity
• Non-Metals

  • Found on the right side of the periodic table
  • Dull appearance
  • Solids or gases at room temperature, except for Bromine (a liquid)
  • Brittle
  • Poor conductors of heat, and electricity
• Metalloids

  • Found between the Metals and Non-metals on the periodic table (along the steps)
  • Shiny of dull in appearance
  • Solids at room temperature
  • Brittle
  • May conduct electricity but are poor conductors of heat
• Chemical Families

  • Alkali Metals
  • Alkaline Earth Metals
  • Halogens
  • Noble Gases
  • Transition Metals
• Alkali Metals

  • Found in group I of the elemental table
  • Very reactive
  • Do not occur freely in nature
  • Are malleable, ductile, and good conductors of heat and electricity
  • Become more reactive as one travels down the column
• Alkaline Earth Metals

  • Found in group 2
  • Very reactive
  • Are not found free in nature
  • Begin with Be (Beryllium)
• Halogens

  • Found in group 17
  • Five non metallic elements
  • "halogen" means "salt-former" and compounds containing halogens are called "salts"
  • Exist, at room temperature, in all three states of matter
  • Begin with F (Fluorine)
• Noble Gases

  • Group 18
  • Rarely react with other elements
  • Very stable
  • Begin with He (Helium)
• Transition Metals

  • Found in group 3-12
  • Are both ductile and malleable, and conduct electricity and heat
  • Less reactive and less metallic than other metals
• Elements in the same horizontal row

  Show trends of increasing or decreasing reactivity
• Rows

  Called periods
• Atomic number is the number of protons and number of electrons in an atom
• Atomic mass is the number of protons plus the number of neutrons in an atom
• To determine the number of neutrons


  Atomic Mass - Atomic Number
• Mass

  1 amu
• Elements are arranged on the periodic table according to increasing atomic number
• From the atomic number and the mass number we can determine the number of protons, neutrons, and electrons in the atom
• Each element has a unique number of protons, neutrons and electrons which gives it unique physical and chemical change
• Atomic Mass


  Number of protons + number of neutrons
• Oxygen

  • Atomic Number: 8, Atomic Mass: 15.999
• Potassium (K)

  • 19 protons, 19 electrons, 20 neutrons
• Neon (Ne)


  • 10 protons, 10 electrons, 10 neutrons
• Information to fill in for an atom

  • Symbol
  • Atomic Number
  • Mass Number
  • Number of Protons
  • Number of Neutrons
  • Number of electrons
• How many protons are in the nucleus of an atom with an atomic number of 15?
• How many neutrons are in the nucleus of an atom with an atomic number of 25?
• What is the mass number of an atom with 3 protons, 4 neutrons, and 3 electrons?
• How many neutrons are in the nucleus of an atom that has an atomic mass of 36 and an atomic number of 25?
• Bohr and Rutherford discovered that the electrons of an atom are arranged in energy shells or orbits around the nucleus
• Shell Maximum

  Each orbit has a maximum number of electrons that it can hold
• Bohr-Rutherford diagrams may be used to create visual representations of atoms
• How to Draw Bohr-Rutherford Diagrams

  1. Draw a circle to represent a nucleus

  2. In this circle write the number of protons and number of neutrons

  3. In circles around the nucleus, draw one dot for each electron in the atom

  4. Electrons should be drawn in pairs except for electrons in the first shell

  5. Once one orbital has reached its 'full' capacity, move onto the next orbital until all electrons are accounted for
• The B-R Diagram of Nitrogen


  • #Protons=7, #Neutrons=7, #Electrons=7
• The B-R Diagram of Fluorine


  • #Protons=9, #Neutrons=10, #Electrons=9
• The B-R Diagram of Magnesium


  • #Protons=12, #Neutrons=12, #Electrons=12
• Most things are not made of individual atoms
• Molecules


  A type of particle made up of two or more atoms that are joined together by a chemical bond
• Molecular Compounds

  Two or more different types of elements chemically joined together