Bonding and Shapes

• Do cations gain or lose electrons ?

  lose
• What ion does metal form ?

  cation
• Write the half equation for Na.

  Na -> Na+ + e-
• Do anions gain or lose electrons ?

  gain
• Write the half equation for Cl.

  Cl + e- -> Cl-
• Definition of ionic bonding.

  The electrostatic force of attraction between positive and negative ions
• Formula for ammonium.

  NH4+
• Formula for posphate.

  PO4*3-
• What does an ionic compound exist as in a solid state ?

  giant ionic lattice
• What compounds contain covalent bonding ?

  non metals
• Definition of covalent bonding.

  The strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms.
• Which elements have less than 8 electrons in their outer shell and do not obey the octate rule ?

  B, Be, Al
• Which elements can have more than 8 electrons in their outer shell and do not obey the octate rule ?

  S, P, Cl, Si
• Why do some elements have more than 8 electrons on their outer shell ?

  Because they have a vacant 3d orbital which can occupy electrons
• Definition of dative covalent bonding.

  A shared pair of electrons which has been provided by one of the bonding atoms only.
• What do bond enthalpies measure ?

  strength of covalent bonds
• What does a high bond enthalpy tell you about the strength of the bond ?

  Strong
• How many bonding/lone pairs exist in a triganol planar and what is the bond angle ?

  Bonding Pairs: 3

  Lone Pairs: 0

  Bond Angle: 120
• How many bonding/lone pairs exist in a tetrahedral and what is the bond angle ?

  Bonding pairs: 4

  Lone pairs: 0

  Bond angle: 109.5
• How many bonding/lone pairs exist in a octahedral and what is the bond angle ?

  Bonding pairs: 6

  Lone Pairs: 0

  Bond Angle: 90
• Why is the tetrahedral shape the most common ?

  Obeys the octate rule but the others don't so they are rare
• How many bonding/lone pairs exist in a pyramidal and what is the bond angle ?

  Bonding Pairs: 3

  Lone Pairs: 1

  Bond Angle: 107
• How many bonding/lone pairs exist in a non linear and what is the bond angle ?

  Bonding Pairs: 2

  Lone Pairs: 2

  Bond Angle: 104.5
• How many degrees does a bond angle repel by for every lone pair ?

  2.5
• How many bonding regions/lone pairs exist in a linear and what is the bond angle ?

  Bonding region: 2

  Lone Pairs: 0

  Bond Angle: 180
• Why is it called a bonding region for linear shapes ?

  It may consist of multiple bonds
• Why do lone pairs repel more than a bonded pair ?

  Because a lone pair is slightly more electron-dense than a bonding pair