Topic 2 - The Periodic Table Flashcards
Periods
Horizontal Rows
- number of shells
Groups
Vertical Columns
- number of electrons in outer shell
Noble Gases
have a full outer shell
- therefore, inert
Electrons
Negatively charged subatomic particles which orbit the nucleus of an atom in shells
Loss of electrons
Positively charged
Gain of electrons
Negatively Charged
Metals always form
CATIONS
Properties of Metals
- good heat conductors
- good electrical conductors
- malleable
- ductile
- sonorous (ring when struck)
- held together by metallic bonds
Transition Metals
- used as catalysts
- share metal properties
- form different coloured solutions
- create ions of different charges
Groups 1,2,6,7
Form ions EASILY
only need to gain/lose a small number of electrons
Groups 3,4,5
Do NOT form ions easily
need to gain/lose a large number of electrons
Magnesium ionisation equation
Mg -> Mg2+ + 2e-
Ionic Bonding
electrostatic forces of attraction between oppositely charged ions
- dot and cross diagrams
Ionic Compounds
- many ionic bonds
- regular 3D lattice structure
Properties of Ionic Compounds
- high melting and boiling points (strong bonds require lots of heat energy)
- conduct electricity when molten or in aqueous solution (free moving ions can carry)
Polyatomic Ions
Hydroxide (OH -)
Sulphate (SO4 2-)
Nitrate (NO3 -)
Carbonate (CO3 2-)
Ammonium (NH4 +)
Covalent Bonding
electrostatic forces of attraction between a shared pair of electrona and the nuclei of atoms involved.
Simple Covalent Substances
- weak intermolecular forces, strong covalent bonds
- low melting and boiling points
- cannot conduct electricity
Characteristics of Diamond
- All four valence electrons used
- Hard
- High melting & boiling point
- Does not conduct electricity
- Used for jewelry and cutting tools
Characteristics of Fullerene C60
- Only 3 valence elecctrons used
- soft
- low melting and boiling point
- conducts electricity (delocalised electrons)
- used for lubricant and drug delivery system in body
Characteristics of Graphite
- only 3 valence electrons used
- soft
- high melting & boiling point
- conducts electricity (delocalised electrons)
- used for lubricant and electrodes
- weak intermolecular forces between layers -> slide over each other
Metal & Nonmetal
Ionic Bonding
Nonmetal & Nonmetal
Covalent Bonding
Metal & Metal
Metallic Bonding